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A Naturalist's Voyage Round the World - The Voyage Of The Beagle
by Charles Darwin
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A NATURALIST'S VOYAGE ROUND THE WORLD

By Charles Darwin



FIRST EDITION...MAY 1860.

SECOND EDITION...MAY 1870.

THIRD EDITION...FEBRUARY 1872.

FOURTH EDITION...JULY 1874.

FIFTH EDITION...MARCH 1876.

SIXTH EDITION...JANUARY 1879.

SEVENTH EDITION...MAY 1882.

EIGHTH EDITION...FEBRUARY 1884.

NINTH EDITION...AUGUST 1886.

TENTH EDITION...JANUARY 1888.

ELEVENTH EDITION...JANUARY 1890.

REPRINTED...JUNE 1913.

(FRONTISPIECE. H.M.S. BEAGLE IN STRAITS OF MAGELLAN. MT. SARMIENTO IN THE DISTANCE.)

JOURNAL OF RESEARCHES

INTO THE

NATURAL HISTORY AND GEOLOGY

OF THE

COUNTRIES VISITED DURING THE VOYAGE ROUND THE WORLD OF H.M.S. 'BEAGLE' UNDER THE COMMAND OF CAPTAIN FITZ ROY, R.N.

BY CHARLES DARWIN, M.A., F.R.S.

AUTHOR OF 'ORIGIN OF SPECIES,' ETC.

(PLATE 1. H.M.S. BEAGLE UNDER FULL SAIL, VIEW FROM ASTERN.)

A NEW EDITION WITH ILLUSTRATIONS BY R.T. PRITCHETT OF PLACES VISITED AND OBJECTS DESCRIBED.

LONDON JOHN MURRAY, ALBEMARLE STREET 1913.



TO CHARLES LYELL, ESQ., F.R.S.,

This second edition is dedicated with grateful pleasure, as an acknowledgment that the chief part of whatever scientific merit this journal and the other works of the author may possess, has been derived from studying the well-known and admirable

PRINCIPLES OF GEOLOGY.



PREFATORY NOTICE TO THE ILLUSTRATED EDITION.

This work was described, on its first appearance, by a writer in the "Quarterly Review" as "One of the most interesting narratives of voyaging that it has fallen to our lot to take up, and one which must always occupy a distinguished place in the history of scientific navigation."

This prophecy has been amply verified by experience; the extraordinary minuteness and accuracy of Mr. Darwin's observations, combined with the charm and simplicity of his descriptions, have ensured the popularity of this book with all classes of readers—and that popularity has even increased in recent years. No attempt, however, has hitherto been made to produce an illustrated edition of this valuable work: numberless places and objects are mentioned and described, but the difficulty of obtaining authentic and original representations of them drawn for the purpose has never been overcome until now.

Most of the views given in this work are from sketches made on the spot by Mr. Pritchett, with Mr. Darwin's book by his side. Some few of the others are taken from engravings which Mr. Darwin had himself selected for their interest as illustrating his voyage, and which have been kindly lent by his son.

Mr. Pritchett's name is well known in connection with the voyages of the "Sunbeam" and "Wanderer," and it is believed that the illustrations, which have been chosen and verified with the utmost care and pains, will greatly add to the value and interest of the "VOYAGE OF A NATURALIST."

JOHN MURRAY. December 1889.



AUTHOR'S PREFACE.

I have stated in the preface to the first Edition of this work, and in the "Zoology of the Voyage of the Beagle," that it was in consequence of a wish expressed by Captain Fitz Roy, of having some scientific person on board, accompanied by an offer from him of giving up part of his own accommodations, that I volunteered my services, which received, through the kindness of the hydrographer, Captain Beaufort, the sanction of the Lords of the Admiralty. As I feel that the opportunities which I enjoyed of studying the Natural History of the different countries we visited have been wholly due to Captain Fitz Roy, I hope I may here be permitted to repeat my expression of gratitude to him; and to add that, during the five years we were together, I received from him the most cordial friendship and steady assistance. Both to Captain Fitz Roy and to all the Officers of the "Beagle" I shall ever feel most thankful for the undeviating kindness with which I was treated during our long voyage. (Preface/1. I must take this opportunity of returning my sincere thanks to Mr. Bynoe, the surgeon of the "Beagle," for his very kind attention to me when I was ill at Valparaiso.)

This volume contains, in the form of a Journal, a history of our voyage, and a sketch of those observations in Natural History and Geology, which I think will possess some interest for the general reader. I have in this edition largely condensed and corrected some parts, and have added a little to others, in order to render the volume more fitted for popular reading; but I trust that naturalists will remember that they must refer for details to the larger publications which comprise the scientific results of the Expedition. The "Zoology of the Voyage of the 'Beagle'" includes an account of the Fossil Mammalia, by Professor Owen; of the Living Mammalia, by Mr. Waterhouse; of the Birds, by Mr. Gould; of the Fish, by the Reverend L. Jenyns; and of the Reptiles, by Mr. Bell. I have appended to the descriptions of each species an account of its habits and range. These works, which I owe to the high talents and disinterested zeal of the above distinguished authors, could not have been undertaken had it not been for the liberality of the Lords Commissioners of Her Majesty's Treasury, who, through the representation of the Right Honourable the Chancellor of the Exchequer, have been pleased to grant a sum of one thousand pounds towards defraying part of the expenses of publication.

I have myself published separate volumes on the "Structure and Distribution of Coral Reefs"; on the "Volcanic Islands visited during the Voyage of the 'Beagle'"; and on the "Geology of South America." The sixth volume of the "Geological Transactions" contains two papers of mine on the Erratic Boulders and Volcanic Phenomena of South America. Messrs. Waterhouse, Walker, Newman, and White, have published several able papers on the Insects which were collected, and I trust that many others will hereafter follow. The plants from the southern parts of America will be given by Dr. J. Hooker, in his great work on the Botany of the Southern Hemisphere. The Flora of the Galapagos Archipelago is the subject of a separate memoir by him, in the "Linnean Transactions." The Reverend Professor Henslow has published a list of the plants collected by me at the Keeling Islands; and the Reverend J.M. Berkeley has described my cryptogamic plants.

I shall have the pleasure of acknowledging the great assistance which I have received from several other naturalists in the course of this and my other works; but I must be here allowed to return my most sincere thanks to the Reverend Professor Henslow, who, when I was an undergraduate at Cambridge, was one chief means of giving me a taste for Natural History,—who, during my absence, took charge of the collections I sent home, and by his correspondence directed my endeavours,—and who, since my return, has constantly rendered me every assistance which the kindest friend could offer.

DOWN, BROMLEY, KENT, June 1845.



CONTENTS.

CHAPTER I.

Porto Praya—Ribeira Grande—Atmospheric Dust with Infusoria —Habits of a Sea-slug and Cuttle-fish—St. Paul's Rocks, non-volcanic—Singular Incrustations—Insects the first Colonists of Islands—Fernando Noronha—Bahia—Burnished Rocks—Habits of a Diodon—Pelagic Confervae and Infusoria— Causes of discoloured Sea.

CHAPTER II.

Rio de Janeiro—Excursion north of Cape Frio—Great Evaporation—Slavery—Botofogo Bay—Terrestrial Planariae —Clouds on the Corcovado—Heavy Rain—Musical Frogs— Phosphorescent insects—Elater, springing powers of—Blue Haze—Noise made by a Butterfly—Entomology—Ants—Wasp killing a Spider—Parasitical Spider—Artifices of an Epeira —Gregarious Spider—Spider with an unsymmetrical web.

CHAPTER III.

Monte Video—Maldonado—Excursion to R. Polanco—Lazo and Bolas—Partridges—Absence of trees—Deer—Capybara, or River Hog—Tucutuco—Molothrus, cuckoo-like habits— Tyrant-flycatcher—Mocking-bird—Carrion Hawks—Tubes formed by lightning—House struck.

CHAPTER IV.

Rio Negro—Estancias attacked by the Indians—Salt-Lakes— Flamingoes—R. Negro to R. Colorado—Sacred Tree— Patagonian Hare—Indian Families—General Rosas—Proceed to Bahia Blanca—Sand Dunes—Negro Lieutenant—Bahia Blanca— Saline incrustations—Punta Alta—Zorillo.

CHAPTER V.

Bahia Blanca—Geology—Numerous gigantic extinct Quadrupeds —Recent Extinction—Longevity of Species—Large Animals do not require a luxuriant vegetation—Southern Africa—Siberian Fossils—Two Species of Ostrich—Habits of Oven-bird— Armadilloes—Venomous Snake, Toad, Lizard—Hybernation of Animals—Habits of Sea-Pen—Indian Wars and Massacres— Arrowhead—Antiquarian Relic.

CHAPTER VI.

Set out for Buenos Ayres—Rio Sauce—Sierra Ventana—Third Posta—Driving Horses—Bolas—Partridges and Foxes— Features of the country—Long-legged Plover—Teru-tero— Hail-storm—Natural enclosures in the Sierra Tapalguen—Flesh of Puma—Meat Diet—Guardia del Monte—Effects of cattle on the Vegetation—Cardoon—Buenos Ayres—Corral where cattle are slaughtered.

CHAPTER VII.

Excursion to St. Fe—Thistle Beds—Habits of the Bizcacha— Little Owl—Saline streams—Level plains—Mastodon—St. Fe—Change in landscape—Geology—Tooth of extinct Horse— Relation of the Fossil and recent Quadrupeds of North and South America—Effects of a great drought—Parana—Habits of the Jaguar—Scissor-beak—Kingfisher, Parrot, and Scissor-tail— Revolution—Buenos Ayres—State of Government.

CHAPTER VIII.

Excursion to Colonia del Sacramiento—Value of an Estancia— Cattle, how counted—Singular breed of Oxen—Perforated pebbles—Shepherd-dogs—Horses broken-in, Gauchos riding— Character of Inhabitants—Rio Plata—Flocks of Butterflies— Aeronaut Spiders—Phosphorescence of the Sea—Port Desire— Guanaco—Port St. Julian—Geology of Patagonia—Fossil gigantic Animal—Types of Organisation constant—Change in the Zoology of America—Causes of Extinction.

CHAPTER IX.

Santa Cruz—Expedition up the River—Indians—Immense streams of basaltic lava—Fragments not transported by the river—Excavation of the valley—Condor, habits of— Cordillera—Erratic boulders of great size—Indian relics— Return to the ship—Falkland Islands—Wild horses, cattle, rabbits—Wolf-like fox—Fire made of bones—Manner of hunting wild cattle—Geology—Streams of stones—Scenes of violence—Penguin—Geese—Eggs of Doris—Compound animals.

CHAPTER X.

Tierra del Fuego, first arrival—Good Success Bay—An account of the Fuegians on board—Interview with the savages—Scenery of the forests—Cape Horn—Wigwam Cove—Miserable condition of the savages—Famines—Cannibals—Matricide—Religious feelings—Great Gale—Beagle Channel—Ponsonby Sound— Build wigwams and settle the Fuegians—Bifurcation of the Beagle Channel—Glaciers—Return to the Ship—Second visit in the Ship to the Settlement—Equality of condition amongst the natives.

CHAPTER XI.

Strait of Magellan—Port Famine—Ascent of Mount Tarn— Forests—Edible fungus—Zoology—Great Seaweed—Leave Tierra del Fuego—Climate—Fruit-trees and productions of the southern coasts—Height of snow-line on the Cordillera— Descent of glaciers to the sea—Icebergs formed—Transportal of boulders—Climate and productions of the Antarctic Islands —Preservation of frozen carcasses—Recapitulation.

CHAPTER XII.

Valparaiso—Excursion to the foot of the Andes—Structure of the land—Ascend the Bell of Quillota—Shattered masses of greenstone—Immense valleys—Mines—State of miners— Santiago—Hot-baths of Cauquenes—Gold-mines— Grinding-mills—Perforated stones—Habits of the Puma—El Turco and Tapacolo—Humming-birds.

CHAPTER XIII.

Chiloe—General aspect—Boat excursion—Native Indians— Castro—Tame fox—Ascend San Pedro—Chonos Archipelago— Peninsula of Tres Montes—Granitic range—Boat-wrecked sailors—Low's Harbour—Wild potato—Formation of peat— Myopotamus, otter and mice—Cheucau and Barking-bird— Opetiorhynchus—Singular character of ornithology—Petrels.

CHAPTER XIV.

San Carlos, Chiloe—Osorno in eruption, contemporaneously with Aconcagua and Coseguina—Ride to Cucao—Impenetrable forests —Valdivia—Indians—Earthquake—Concepcion—Great earthquake—Rocks fissured—Appearance of the former towns— The sea black and boiling—Direction of the vibrations— Stones twisted round—Great Wave—Permanent Elevation of the land—Area of volcanic phenomena—The connection between the elevatory and eruptive forces—Cause of earthquakes—Slow elevation of mountain-chains.

CHAPTER XV.

Valparaiso—Portillo Pass—Sagacity of mules— Mountain-torrents—Mines, how discovered—Proofs of the gradual elevation of the Cordillera—Effect of snow on rocks— Geological structure of the two main ranges, their distinct origin and upheaval—Great subsidence—Red snow—Winds— Pinnacles of snow—Dry and clear atmosphere—Electricity— Pampas—Zoology of the opposite sides of the Andes—Locusts —Great Bugs—Mendoza—Uspallata Pass—Silicified trees buried as they grew—Incas Bridge—Badness of the passes exaggerated—Cumbre—Casuchas—Valparaiso.

CHAPTER XVI.

Coast-road to Coquimbo—Great loads carried by the miners— Coquimbo—Earthquake—Step-formed terraces—Absence of recent deposits—Contemporaneousness of the Tertiary formations —Excursion up the valley—Road to Guasco—Deserts—Valley of Copiapo—Rain and Earthquakes—Hydrophobia—The Despoblado—Indian ruins—Probable change of climate— River-bed arched by an earthquake—Cold gales of wind—Noises from a hill—Iquique—Salt alluvium—Nitrate of soda— Lima—Unhealthy country—Ruins of Callao, overthrown by an earthquake—Recent subsidence—Elevated shells on San Lorenzo, their decomposition—Plain with embedded shells and fragments of pottery—Antiquity of the Indian Race.

CHAPTER XVII.

Galapagos Archipelago—The whole group volcanic—Number of craters—Leafless bushes—Colony at Charles Island—James Island—Salt-lake in crater—Natural history of the group— Ornithology, curious finches—Reptiles—Great tortoises, habits of—Marine lizard, feeds on seaweed—Terrestrial lizard, burrowing habits, herbivorous—Importance of reptiles in the Archipelago—Fish, shells, insects—Botany—American type of organisation—Differences in the species or races on different islands—Tameness of the birds—Fear of man an acquired instinct.

CHAPTER XVIII.

Pass through the Low Archipelago—Tahiti—Aspect— Vegetation on the mountains—View of Eimeo—Excursion into the interior—Profound ravines—Succession of waterfalls— Number of wild useful plants—Temperance of the inhabitants— Their moral state—Parliament convened—New Zealand—Bay of Islands—Hippahs—Excursion to Waimate—Missionary establishment—English weeds now run wild—Waiomio—Funeral of a New Zealand woman—Sail for Australia.

CHAPTER XIX.

Sydney—Excursion to Bathurst—Aspect of the woods—Party of natives—Gradual extinction of the aborigines—Infection generated by associated men in health—Blue Mountains—View of the grand gulf-like valleys—Their origin and formation— Bathurst, general civility of the lower orders—State of Society—Van Diemen's Land—Hobart Town—Aborigines all banished—Mount Wellington—King George's Sound—Cheerless aspect of the country—Bald Head, calcareous casts of branches of trees—Party of natives—Leave Australia.

CHAPTER XX.

Keeling Island—Singular appearance—Scanty Flora— Transport of seeds—Birds and insects—Ebbing and flowing springs—Fields of dead coral—Stones transported in the roots of trees—Great crab—Stinging corals—Coral-eating fish—Coral formations—Lagoon islands or atolls—Depth at which reef-building corals can live—Vast areas interspersed with low coral islands—Subsidence of their foundations— Barrier-reefs—Fringing-reefs—Conversion of fringing-reefs into barrier-reefs, and into atolls—Evidence of changes in level—Breaches in barrier-reefs—Maldiva atolls, their peculiar structure—Dead and submerged reefs—Areas of subsidence and elevation—Distribution of volcanoes— Subsidence slow and vast in amount.

CHAPTER XXI.

Mauritius, beautiful appearance of—Great crateriform ring of mountains—Hindoos—St. Helena—History of the changes in the vegetation—Cause of the extinction of land-shells— Ascension—Variation in the imported rats—Volcanic bombs— Beds of infusoria—Bahia, Brazil—Splendour of tropical scenery—Pernambuco—Singular reefs—Slavery—Return to England—Retrospect on our voyage.

INDEX.

.....

LIST OF ILLUSTRATIONS.

FRONTISPIECE. H.M.S. "BEAGLE" IN STRAITS OF MAGELLAN. MT. SARMIENTO IN THE DISTANCE.

PLATE 1. H.M.S. "BEAGLE" UNDER FULL SAIL, VIEW FROM ASTERN.

PLATE 2. H.M.S. "BEAGLE": MIDDLE SECTION FORE AND AFT, UPPER DECK, 1832.

PLATE 3. FERNANDO NORONHA.

PLATE 4. INCRUSTATION OF SHELLY SAND.

PLATE 5. DIODON MACULATUS (Distended and Contracted).

PLATE 6. PELAGIC CONFERVAE.

PLATE 7. CATAMARAN (BAHIA).

PLATE 8. BOTOFOGO BAY, RIO DE JANEIRO.

PLATE 9. VAMPIRE BAT (Desmodus D'Orbigny).

PLATE 10. VIRGIN FOREST.

PLATE 11. CABBAGE PALM.

PLATE 12. MANDIOCA OR CASSAVA.

PLATE 13. RIO DE JANEIRO.

PLATE 14. DARWIN'S PAPILIO FERONIA, 1833, NOW CALLED AGERONIA FERONIA, 1889.

PLATE 15. HYDROCHAERUS CAPYBARA OR WATER-HOG.

PLATE 16. RECADO OR SURCINGLE OF GAUCHO.

PLATE 17. HALT AT A PULPERIA ON THE PAMPAS.

PLATE 18. EL CARMEN, OR PATAGONES, RIO NEGRO.

PLATE 19. BRAZILIAN WHIPS, HOBBLES, AND SPURS.

PLATE 20. BRINGING IN A PRISONER.

PLATE 21. IRREGULAR TROOPS.

PLATE 22. SKINNING UJI OR WATER SERPENTS.

PLATE 23. RHEA DARWINII (Avestruz Petise).

PLATE 24. LANDING AT BUENOS AYRES.

PLATE 25. MATE POTS AND BAMBILLIO.

PLATE 26. GIANT THISTLE OF PAMPAS.

PLATE 27. CYNARA CARDUNCULUS OR CARDOON.

PLATE 28. EVENING CAMP, BUENOS AYRES.

PLATE 29. ROZARIO.

PLATE 30. PARANA RIVER.

PLATE 31. TOXODON PLATENSIS. (Found at Saladillo.)

PLATE 32. FOSSIL TOOTH OF HORSE. (From Bahia Blanca.)

PLATE 33. MYLODON.

PLATE 34. HEAD OF SCISSOR-BEAK.

PLATE 35. RHYNCHOPS NIGRA, OR SCISSOR-BEAK.

PLATE 36. BUENOS AYRES BULLOCK-WAGGONS.

PLATE 37. FUEGIANS AND WIGWAMS.

PLATE 38. OPUNTIA DARWINII.

PLATE 39. RAISED BEACHES, PATAGONIA.

PLATE 40. LADIES' COMBS, BANDA ORIENTAL.

PLATE 41. CONDOR (Sarcorhamphus gryphus).

PLATE 42. BASALTIC GLEN, SANTA CRUZ.

PLATE 43. BERKELEY SOUND, FALKLAND ISLANDS.

PLATE 44. YORK MINSTER (Bearing south 66 degrees east.)

PLATE 45. CAPE HORN.

PLATE 46. CAPE HORN (Another view).

PLATE 47. BAD WEATHER, MAGELLAN STRAITS.

PLATE 48. FUEGIAN BASKET AND BONE WEAPONS.

PLATE 49. FALSE HORN, CAPE HORN.

PLATE 50. WOLLASTON ISLAND, TIERRA DEL FUEGO.

PLATE 51. PATAGONIANS FROM CAPE GREGORY.

PLATE 52. PORT FAMINE, MAGELLAN.

PLATE 53. PATAGONIAN BOLAS.

PLATE 54. PATAGONIAN SPURS AND PIPE.

PLATE 55. CYTTARIA DARWINII.

PLATE 56. EYRE SOUND.

PLATE 57. GLACIER IN GULF OF PENAS.

PLATE 58. FLORA OF MAGELLAN.

PLATE 59. MACROCYSTIS PYRIFERA, OR MAGELLAN KELP.

PLATE 60. TROCHILUS FORFICATUS.

PLATE 61. HACIENDA, CONDOR, CACTUS, ETC.

PLATE 62. CHILIAN MINER.

PLATE 63. CACTUS (Cereus Peruviana).

PLATE 64. CORDILLERAS FROM SANTIAGO DE CHILE.

PLATE 65. CHILIAN SPURS, STIRRUP, ETC.

PLATE 66. OLD CHURCH, CASTRO, CHILOE.

PLATE 67. INSIDE CHONOS ARCHIPELAGO.

PLATE 68. GUNNERA SCABRA, CHILOE.

PLATE 69. ANTUCO VOLCANO, NEAR TALCAHUANO.

PLATE 70. PANORAMIC VIEW OF COAST, CHILOE.

PLATE 71. INSIDE ISLAND OF CHILOE. SAN CARLOS.

PLATE 72. HIDE BRIDGE, SANTIAGO DE CHILE.

PLATE 73. CHILENOS.

PLATE 74. SOUTH AMERICAN BIT.

PLATE 75. BRIDGE OF THE INCAS, USPALLATA PASS.

PLATE 76. LIMA AND SAN LORENZO.

PLATE 77. COQUIMBO, CHILE.

PLATE 78. HUACAS, PERUVIAN POTTERY.

PLATE 79. TESTUDO ABINGDONII, GALAPAGOS ISLANDS.

PLATE 80. GALAPAGOS ARCHIPELAGO.

PLATE 81. FINCHES FROM GALAPAGOS ARCHIPELAGO.

PLATE 82. AMBLYRHYNCHUS CRISTATUS.

PLATE 83. OPUNTIA GALAPAGEIA.

PLATE 84. AVA OR KAVA (Macropiper methysticum), TAHITI.

PLATE 85. EIMEO AND BARRIER-REEF.

PLATE 86. FATAHUA FALL, TAHITI.

PLATE 87. TAHITIAN.

PLATE 88. HIPPAH, NEW ZEALAND.

PLATE 89. SYDNEY, 1835.

PLATE 90. HOBART TOWN AND MOUNT WELLINGTON.

PLATE 91. AUSTRALIAN GROUP OF WEAPONS AND THROWING STICKS.

PLATE 92. INSIDE AN ATOLL, KEELING ISLAND.

PLATE 93. WHITSUNDAY ISLAND.

PLATE 94. BARRIER-REEF, BOLABOLA.

PLATE 95. SECTIONS OF BARRIER-REEFS.

PLATE 96. SECTION OF CORAL-REEF.

PLATE 97. SECTION OF CORAL-REEF.

PLATE 98. BOLABOLA ISLAND.

PLATE 99. CORALS.

PLATE 100. BIRGOS LATRO, KEELING ISLAND.

PLATE 101. ST. LOUIS, MAURITIUS.

PLATE 102. ST. HELENA.

PLATE 103. CELLULAR FORMATION OF VOLCANIC BOMB.

PLATE 104. CICADA HOMOPTERA.

PLATE 105. HOMEWARD BOUND.

PLATE 106. ASCENSION. TERNS AND NODDIES.

PLATE 107. MAP OF SOUTH AMERICA.

PLATE 108. MAP OF THE WORLD, SHOWING THE TRACK OF H.M.S. "BEAGLE."

...

(PLATE 2. H.M.S. "BEAGLE": MIDDLE SECTION FORE AND AFT, UPPER DECK, 1832.)

(PLATE 3. FERNANDO NORONHA.)



JOURNAL.



CHAPTER I.

Porto Praya. Ribeira Grande. Atmospheric Dust with Infusoria. Habits of a Sea-slug and Cuttle-fish. St. Paul's Rocks, non-volcanic. Singular Incrustations. Insects the first Colonists of Islands. Fernando Noronha. Bahia. Burnished Rocks. Habits of a Diodon. Pelagic Confervae and Infusoria. Causes of discoloured Sea.

ST. JAGO—CAPE DE VERD ISLANDS.



After having been twice driven back by heavy south-western gales, Her Majesty's ship "Beagle," a ten-gun brig, under the command of Captain Fitz Roy, R.N., sailed from Devonport on the 27th of December, 1831. The object of the expedition was to complete the survey of Patagonia and Tierra del Fuego, commenced under Captain King in 1826 to 1830—to survey the shores of Chile, Peru, and of some islands in the Pacific—and to carry a chain of chronometrical measurements round the World. On the 6th of January we reached Teneriffe, but were prevented landing, by fears of our bringing the cholera: the next morning we saw the sun rise behind the rugged outline of the Grand Canary Island, and suddenly illumine the Peak of Teneriffe, whilst the lower parts were veiled in fleecy clouds. This was the first of many delightful days never to be forgotten. On the 16th of January 1832 we anchored at Porto Praya, in St. Jago, the chief island of the Cape de Verd archipelago.

The neighbourhood of Porto Praya, viewed from the sea, wears a desolate aspect. The volcanic fires of a past age, and the scorching heat of a tropical sun, have in most places rendered the soil unfit for vegetation. The country rises in successive steps of table-land, interspersed with some truncate conical hills, and the horizon is bounded by an irregular chain of more lofty mountains. The scene, as beheld through the hazy atmosphere of this climate, is one of great interest; if, indeed, a person, fresh from sea, and who has just walked, for the first time, in a grove of cocoa-nut trees, can be a judge of anything but his own happiness. The island would generally be considered as very uninteresting, but to any one accustomed only to an English landscape, the novel aspect of an utterly sterile land possesses a grandeur which more vegetation might spoil. A single green leaf can scarcely be discovered over wide tracts of the lava plains; yet flocks of goats, together with a few cows, contrive to exist. It rains very seldom, but during a short portion of the year heavy torrents fall, and immediately afterwards a light vegetation springs out of every crevice. This soon withers; and upon such naturally formed hay the animals live. It had not now rained for an entire year. When the island was discovered, the immediate neighbourhood of Porto Praya was clothed with trees (1/1. I state this on the authority of Dr. E. Dieffenbach, in his German translation of the first edition of this Journal.), the reckless destruction of which has caused here, as at St. Helena, and at some of the Canary islands, almost entire sterility. The broad, flat-bottomed valleys, many of which serve during a few days only in the season as watercourses, are clothed with thickets of leafless bushes. Few living creatures inhabit these valleys. The commonest bird is a kingfisher (Dacelo Iagoensis), which tamely sits on the branches of the castor-oil plant, and thence darts on grasshoppers and lizards. It is brightly coloured, but not so beautiful as the European species: in its flight, manners, and place of habitation, which is generally in the driest valley, there is also a wide difference.

One day, two of the officers and myself rode to Ribeira Grande, a village a few miles eastward of Porto Praya. Until we reached the valley of St. Martin, the country presented its usual dull brown appearance; but here, a very small rill of water produces a most refreshing margin of luxuriant vegetation. In the course of an hour we arrived at Ribeira Grande, and were surprised at the sight of a large ruined fort and cathedral. This little town, before its harbour was filled up, was the principal place in the island: it now presents a melancholy, but very picturesque appearance. Having procured a black Padre for a guide, and a Spaniard who had served in the Peninsular war as an interpreter, we visited a collection of buildings, of which an ancient church formed the principal part. It is here the governors and captain-generals of the islands have been buried. Some of the tombstones recorded dates of the sixteenth century. (1/2. The Cape de Verd Islands were discovered in 1449. There was a tombstone of a bishop with the date of 1571; and a crest of a hand and dagger, dated 1497.) The heraldic ornaments were the only things in this retired place that reminded us of Europe. The church or chapel formed one side of a quadrangle, in the middle of which a large clump of bananas were growing. On another side was a hospital, containing about a dozen miserable-looking inmates.

We returned to the Venda to eat our dinners. A considerable number of men, women, and children, all as black as jet, collected to watch us. Our companions were extremely merry; and everything we said or did was followed by their hearty laughter. Before leaving the town we visited the cathedral. It does not appear so rich as the smaller church, but boasts of a little organ, which sent forth singularly inharmonious cries. We presented the black priest with a few shillings, and the Spaniard, patting him on the head, said, with much candour, he thought his colour made no great difference. We then returned, as fast as the ponies would go, to Porto Praya.

Another day we rode to the village of St. Domingo, situated near the centre of the island. On a small plain which we crossed, a few stunted acacias were growing; their tops had been bent by the steady trade-wind, in a singular manner—some of them even at right angles to their trunks. The direction of the branches was exactly north-east by north, and south-west by south, and these natural vanes must indicate the prevailing direction of the force of the trade-wind. The travelling had made so little impression on the barren soil, that we here missed our track, and took that to Fuentes. This we did not find out till we arrived there; and we were afterwards glad of our mistake. Fuentes is a pretty village, with a small stream; and everything appeared to prosper well, excepting, indeed, that which ought to do so most—its inhabitants. The black children, completely naked, and looking very wretched, were carrying bundles of firewood half as big as their own bodies.

Near Fuentes we saw a large flock of guinea-fowl—probably fifty or sixty in number. They were extremely wary, and could not be approached. They avoided us, like partridges on a rainy day in September, running with their heads cocked up; and if pursued, they readily took to the wing.

The scenery of St. Domingo possesses a beauty totally unexpected, from the prevalent gloomy character of the rest of the island. The village is situated at the bottom of a valley, bounded by lofty and jagged walls of stratified lava. The black rocks afford a most striking contrast with the bright green vegetation, which follows the banks of a little stream of clear water. It happened to be a grand feast-day, and the village was full of people. On our return we overtook a party of about twenty young black girls, dressed in excellent taste; their black skins and snow-white linen being set off by coloured turbans and large shawls. As soon as we approached near, they suddenly all turned round, and covering the path with their shawls, sung with great energy a wild song, beating time with their hands upon their legs. We threw them some vintems, which were received with screams of laughter, and we left them redoubling the noise of their song.

One morning the view was singularly clear; the distant mountains being projected with the sharpest outline, on a heavy bank of dark blue clouds. Judging from the appearance, and from similar cases in England, I supposed that the air was saturated with moisture. The fact, however, turned out quite the contrary. The hygrometer gave a difference of 29.6 degrees, between the temperature of the air, and the point at which dew was precipitated. This difference was nearly double that which I had observed on the previous mornings. This unusual degree of atmospheric dryness was accompanied by continual flashes of lightning. Is it not an uncommon case, thus to find a remarkable degree of aerial transparency with such a state of weather?

Generally the atmosphere is hazy; and this is caused by the falling of impalpably fine dust, which was found to have slightly injured the astronomical instruments. The morning before we anchored at Porto Praya, I collected a little packet of this brown-coloured fine dust, which appeared to have been filtered from the wind by the gauze of the vane at the masthead. Mr. Lyell has also given me four packets of dust which fell on a vessel a few hundred miles northward of these islands. Professor Ehrenberg finds that this dust consists in great part of infusoria with siliceous shields, and of the siliceous tissue of plants. (1/3. I must take this opportunity of acknowledging the great kindness with which this illustrious naturalist has examined many of my specimens. I have sent (June 1845) a full account of the falling of this dust to the Geological Society.) In five little packets which I sent him, he has ascertained no less than sixty-seven different organic forms! The infusoria, with the exception of two marine species, are all inhabitants of fresh-water. I have found no less than fifteen different accounts of dust having fallen on vessels when far out in the Atlantic. From the direction of the wind whenever it has fallen, and from its having always fallen during those months when the harmattan is known to raise clouds of dust high into the atmosphere, we may feel sure that it all comes from Africa. It is, however, a very singular fact, that, although Professor Ehrenberg knows many species of infusoria peculiar to Africa, he finds none of these in the dust which I sent him. On the other hand, he finds in it two species which hitherto he knows as living only in South America. The dust falls in such quantities as to dirty everything on board, and to hurt people's eyes; vessels even have run on shore owing to the obscurity of the atmosphere. It has often fallen on ships when several hundred, and even more than a thousand miles from the coast of Africa, and at points sixteen hundred miles distant in a north and south direction. In some dust which was collected on a vessel three hundred miles from the land, I was much surprised to find particles of stone above the thousandth of an inch square, mixed with finer matter. After this fact one need not be surprised at the diffusion of the far lighter and smaller sporules of cryptogamic plants.

The geology of this island is the most interesting part of its natural history. On entering the harbour, a perfectly horizontal white band in the face of the sea cliff, may be seen running for some miles along the coast, and at the height of about forty-five feet above the water. Upon examination, this white stratum is found to consist of calcareous matter, with numerous shells embedded, most or all of which now exist on the neighbouring coast. It rests on ancient volcanic rocks, and has been covered by a stream of basalt, which must have entered the sea when the white shelly bed was lying at the bottom. It is interesting to trace the changes, produced by the heat of the overlying lava, on the friable mass, which in parts has been converted into a crystalline limestone, and in other parts into a compact spotted stone. Where the lime has been caught up by the scoriaceous fragments of the lower surface of the stream, it is converted into groups of beautifully radiated fibres resembling arragonite. The beds of lava rise in successive gently-sloping plains, towards the interior, whence the deluges of melted stone have originally proceeded. Within historical times no signs of volcanic activity have, I believe, been manifested in any part of St. Jago. Even the form of a crater can but rarely be discovered on the summits of the many red cindery hills; yet the more recent streams can be distinguished on the coast, forming lines of cliffs of less height, but stretching out in advance of those belonging to an older series: the height of the cliffs thus affording a rude measure of the age of the streams.

During our stay, I observed the habits of some marine animals. A large Aplysia is very common. This sea-slug is about five inches long; and is of a dirty yellowish colour, veined with purple. On each side of the lower surface, or foot, there is a broad membrane, which appears sometimes to act as a ventilator, in causing a current of water to flow over the dorsal branchiae or lungs. It feeds on the delicate seaweeds which grow among the stones in muddy and shallow water; and I found in its stomach several small pebbles, as in the gizzard of a bird. This slug, when disturbed, emits a very fine purplish-red fluid, which stains the water for the space of a foot around. Besides this means of defence, an acrid secretion, which is spread over its body, causes a sharp, stinging sensation, similar to that produced by the Physalia, or Portuguese man-of-war.

I was much interested, on several occasions, by watching the habits of an Octopus, or cuttle-fish. Although common in the pools of water left by the retiring tide, these animals were not easily caught. By means of their long arms and suckers, they could drag their bodies into very narrow crevices; and when thus fixed, it required great force to remove them. At other times they darted tail first, with the rapidity of an arrow, from one side of the pool to the other, at the same instant discolouring the water with a dark chestnut-brown ink. These animals also escape detection by a very extraordinary, chameleon-like power of changing their colour. They appear to vary their tints according to the nature of the ground over which they pass: when in deep water, their general shade was brownish purple, but when placed on the land, or in shallow water, this dark tint changed into one of a yellowish green. The colour, examined more carefully, was a French grey, with numerous minute spots of bright yellow: the former of these varied in intensity; the latter entirely disappeared and appeared again by turns. These changes were effected in such a manner that clouds, varying in tint between a hyacinth red and a chestnut-brown, were continually passing over the body. (1/4. So named according to Patrick Symes's nomenclature.) Any part, being subjected to a slight shock of galvanism, became almost black: a similar effect, but in a less degree, was produced by scratching the skin with a needle. These clouds, or blushes as they may be called, are said to be produced by the alternate expansion and contraction of minute vesicles containing variously coloured fluids. (1/5. See "Encyclopedia of Anatomy and Physiology" article "Cephalopoda.")

This cuttle-fish displayed its chameleon-like power both during the act of swimming and whilst remaining stationary at the bottom. I was much amused by the various arts to escape detection used by one individual, which seemed fully aware that I was watching it. Remaining for a time motionless, it would then stealthily advance an inch or two, like a cat after a mouse; sometimes changing its colour: it thus proceeded, till having gained a deeper part, it darted away, leaving a dusky train of ink to hide the hole into which it had crawled.

While looking for marine animals, with my head about two feet above the rocky shore, I was more than once saluted by a jet of water, accompanied by a slight grating noise. At first I could not think what it was, but afterwards I found out that it was this cuttle-fish, which, though concealed in a hole, thus often led me to its discovery. That it possesses the power of ejecting water there is no doubt, and it appeared to me that it could certainly take good aim by directing the tube or siphon on the under side of its body. From the difficulty which these animals have in carrying their heads, they cannot crawl with ease when placed on the ground. I observed that one which I kept in the cabin was slightly phosphorescent in the dark.

ST. PAUL'S ROCKS.

In crossing the Atlantic we hove-to, during the morning of February 16th, 1832, close to the island of St. Paul's. This cluster of rocks is situated in 0 degrees 58' north latitude, and 29 degrees 15' west longitude. It is 540 miles distant from the coast of America, and 350 from the island of Fernando Noronha. The highest point is only fifty feet above the level of the sea, and the entire circumference is under three-quarters of a mile. This small point rises abruptly out of the depths of the ocean. Its mineralogical constitution is not simple; in some parts the rock is of a cherty, in others of a feldspathic nature, including thin veins of serpentine. It is a remarkable fact that all the many small islands, lying far from any continent, in the Pacific, Indian, and Atlantic Oceans, with the exception of the Seychelles and this little point of rock, are, I believe, composed either of coral or of erupted matter. The volcanic nature of these oceanic islands is evidently an extension of that law, and the effect of those same causes, whether chemical or mechanical, from which it results that a vast majority of the volcanoes now in action stand either near sea-coasts or as islands in the midst of the sea.

(PLATE 4. INCRUSTATION OF SHELLY SAND.)

The rocks of St. Paul appear from a distance of a brilliantly white colour. This is partly owing to the dung of a vast multitude of seafowl, and partly to a coating of a hard glossy substance with a pearly lustre, which is intimately united to the surface of the rocks. This, when examined with a lens, is found to consist of numerous exceedingly thin layers, its total thickness being about the tenth of an inch. It contains much animal matter, and its origin, no doubt, is due to the action of the rain or spray on the birds' dung. Below some small masses of guano at Ascension, and on the Abrolhos Islets, I found certain stalactitic branching bodies, formed apparently in the same manner as the thin white coating on these rocks. The branching bodies so closely resembled in general appearance certain nulliporae (a family of hard calcareous sea-plants), that in lately looking hastily over my collection I did not perceive the difference. The globular extremities of the branches are of a pearly texture, like the enamel of teeth, but so hard as just to scratch plate-glass. I may here mention, that on a part of the coast of Ascension, where there is a vast accumulation of shelly sand, an incrustation is deposited on the tidal rocks, by the water of the sea, resembling, as represented in Plate 4, certain cryptogamic plants (Marchantiae) often seen on damp walls. The surface of the fronds is beautifully glossy; and those parts formed where fully exposed to the light, are of a jet black colour, but those shaded under ledges are only grey. I have shown specimens of this incrustation to several geologists, and they all thought that they were of volcanic or igneous origin! In its hardness and translucency—in its polish, equal to that of the finest oliva-shell—in the bad smell given out, and loss of colour under the blowpipe—it shows a close similarity with living sea-shells. Moreover in sea-shells, it is known that the parts habitually covered and shaded by the mantle of the animal, are of a paler colour than those fully exposed to the light, just as is the case with this incrustation. When we remember that lime, either as a phosphate or carbonate, enters into the composition of the hard parts, such as bones and shells, of all living animals, it is an interesting physiological fact to find substances harder than the enamel of teeth, and coloured surfaces as well polished as those of a fresh shell, re-formed through inorganic means from dead organic matter—mocking, also, in shape, some of the lower vegetable productions. (1/6. Mr. Horner and Sir David Brewster have described ("Philosophical Transactions" 1836 page 65) a singular "artificial substance resembling shell." It is deposited in fine, transparent, highly polished, brown-coloured laminae, possessing peculiar optical properties, on the inside of a vessel, in which cloth, first prepared with glue and then with lime, is made to revolve rapidly in water. It is much softer, more transparent, and contains more animal matter, than the natural incrustation at Ascension; but we here again see the strong tendency which carbonate of lime and animal matter evince to form a solid substance allied to shell.)

We found on St. Paul's only two kinds of birds—the booby and the noddy. The former is a species of gannet, and the latter a tern. Both are of a tame and stupid disposition, and are so unaccustomed to visitors, that I could have killed any number of them with my geological hammer. The booby lays her eggs on the bare rock; but the tern makes a very simple nest with seaweed. By the side of many of these nests a small flying-fish was placed; which I suppose, had been brought by the male bird for its partner. It was amusing to watch how quickly a large and active crab (Graspus), which inhabits the crevices of the rock, stole the fish from the side of the nest, as soon as we had disturbed the parent birds. Sir W. Symonds, one of the few persons who have landed here, informs me that he saw the crabs dragging even the young birds out of their nests, and devouring them. Not a single plant, not even a lichen, grows on this islet; yet it is inhabited by several insects and spiders. The following list completes, I believe, the terrestrial fauna: a fly (Olfersia) living on the booby, and a tick which must have come here as a parasite on the birds; a small brown moth, belonging to a genus that feeds on feathers; a beetle (Quedius) and a woodlouse from beneath the dung; and lastly, numerous spiders, which I suppose prey on these small attendants and scavengers of the waterfowl. The often-repeated description of the stately palm and other noble tropical plants, then birds, and lastly man, taking possession of the coral islets as soon as formed, in the Pacific, is probably not quite correct; I fear it destroys the poetry of this story, that feather and dirt-feeding and parasitic insects and spiders should be the first inhabitants of newly formed oceanic land.

The smallest rock in the tropical seas, by giving a foundation for the growth of innumerable kinds of seaweed and compound animals, supports likewise a large number of fish. The sharks and the seamen in the boats maintained a constant struggle which should secure the greater share of the prey caught by the fishing-lines. I have heard that a rock near the Bermudas, lying many miles out at sea, and at a considerable depth, was first discovered by the circumstance of fish having been observed in the neighbourhood.

FERNANDO NORONHA, FEBRUARY 20, 1832.

As far as I was enabled to observe, during the few hours we stayed at this place, the constitution of the island is volcanic, but probably not of a recent date. The most remarkable feature is a conical hill, about one thousand feet high, the upper part of which is exceedingly steep, and on one side overhangs its base. The rock is phonolite, and is divided into irregular columns. On viewing one of these isolated masses, at first one is inclined to believe that it has been suddenly pushed up in a semi-fluid state. At St. Helena, however, I ascertained that some pinnacles, of a nearly similar figure and constitution, had been formed by the injection of melted rock into yielding strata, which thus had formed the moulds for these gigantic obelisks. The whole island is covered with wood; but from the dryness of the climate there is no appearance of luxuriance. Half-way up the mountain some great masses of the columnar rock, shaded by laurel-like trees, and ornamented by others covered with fine pink flowers but without a single leaf, gave a pleasing effect to the nearer parts of the scenery.

BAHIA, OR SAN SALVADOR. BRAZIL, FEBRUARY 29, 1832.

The day has past delightfully. Delight itself, however, is a weak term to express the feelings of a naturalist who, for the first time, has wandered by himself in a Brazilian forest. The elegance of the grasses, the novelty of the parasitical plants, the beauty of the flowers, the glossy green of the foliage, but above all the general luxuriance of the vegetation, filled me with admiration. A most paradoxical mixture of sound and silence pervades the shady parts of the wood. The noise from the insects is so loud, that it may be heard even in a vessel anchored several hundred yards from the shore; yet within the recesses of the forest a universal silence appears to reign. To a person fond of natural history, such a day as this brings with it a deeper pleasure than he can ever hope to experience again. After wandering about for some hours, I returned to the landing-place; but, before reaching it, I was overtaken by a tropical storm. I tried to find shelter under a tree, which was so thick that it would never have been penetrated by common English rain; but here, in a couple of minutes, a little torrent flowed down the trunk. It is to this violence of the rain that we must attribute the verdure at the bottom of the thickest woods: if the showers were like those of a colder clime, the greater part would be absorbed or evaporated before it reached the ground. I will not at present attempt to describe the gaudy scenery of this noble bay, because, in our homeward voyage, we called here a second time, and I shall then have occasion to remark on it.

Along the whole coast of Brazil, for a length of at least 2000 miles, and certainly for a considerable space inland, wherever solid rock occurs, it belongs to a granitic formation. The circumstance of this enormous area being constituted of materials which most geologists believe to have been crystallised when heated under pressure, gives rise to many curious reflections. Was this effect produced beneath the depths of a profound ocean? or did a covering of strata formerly extend over it, which has since been removed? Can we believe that any power, acting for a time short of infinity, could have denuded the granite over so many thousand square leagues?

On a point not far from the city, where a rivulet entered the sea, I observed a fact connected with a subject discussed by Humboldt. (1/7. "Personal Narrative" volume 5 part 1 page 18.) At the cataracts of the great rivers Orinoco, Nile, and Congo, the syenitic rocks are coated by a black substance, appearing as if they had been polished with plumbago. The layer is of extreme thinness; and on analysis by Berzelius it was found to consist of the oxides of manganese and iron. In the Orinoco it occurs on the rocks periodically washed by the floods, and in those parts alone where the stream is rapid; or, as the Indians say, "the rocks are black where the waters are white." Here the coating is of a rich brown instead of a black colour, and seems to be composed of ferruginous matter alone. Hand specimens fail to give a just idea of these brown burnished stones which glitter in the sun's rays. They occur only within the limits of the tidal waves; and as the rivulet slowly trickles down, the surf must supply the polishing power of the cataracts in the great rivers. In like manner, the rise and fall of the tide probably answer to the periodical inundations; and thus the same effects are produced under apparently different but really similar circumstances. The origin, however, of these coatings of metallic oxides, which seem as if cemented to the rocks, is not understood; and no reason, I believe, can be assigned for their thickness remaining the same.

(PLATE 5. DIODON MACULATUS (DISTENDED AND CONTRACTED).)

One day I was amused by watching the habits of the Diodon antennatus, which was caught swimming near the shore. This fish, with its flabby skin, is well known to possess the singular power of distending itself into a nearly spherical form. After having been taken out of water for a short time, and then again immersed in it, a considerable quantity both of water and air is absorbed by the mouth, and perhaps likewise by the branchial orifices. This process is effected by two methods: the air is swallowed, and is then forced into the cavity of the body, its return being prevented by a muscular contraction which is externally visible: but the water enters in a gentle stream through the mouth, which is kept wide open and motionless; this latter action must, therefore, depend on suction. The skin about the abdomen is much looser than that on the back; hence, during the inflation, the lower surface becomes far more distended than the upper; and the fish, in consequence, floats with its back downwards. Cuvier doubts whether the Diodon in this position is able to swim; but not only can it thus move forward in a straight line, but it can turn round to either side. This latter movement is effected solely by the aid of the pectoral fins; the tail being collapsed and not used. From the body being buoyed up with so much air, the branchial openings are out of water, but a stream drawn in by the mouth constantly flows through them.

The fish, having remained in this distended state for a short time, generally expelled the air and water with considerable force from the branchial apertures and mouth. It could emit, at will, a certain portion of the water, and it appears, therefore probable that this fluid is taken in partly for the sake of regulating its specific gravity. This Diodon possessed several means of defence. It could give a severe bite, and could eject water from its mouth to some distance, at the same time making a curious noise by the movement of its jaws. By the inflation of its body, the papillae, with which the skin is covered, become erect and pointed. But the most curious circumstance is, that it secretes from the skin of its belly, when handled, a most beautiful carmine-red fibrous matter, which stains ivory and paper in so permanent a manner, that the tint is retained with all its brightness to the present day: I am quite ignorant of the nature and use of this secretion. I have heard from Dr. Allan of Forres, that he has frequently found a Diodon, floating alive and distended, in the stomach of the shark; and that on several occasions he has known it eat its way, not only through the coats of the stomach, but through the sides of the monster, which has thus been killed. Who would ever have imagined that a little soft fish could have destroyed the great and savage shark?

MARCH 18, 1832.

(PLATE 6. PELAGIC CONFERVAE.)

We sailed from Bahia. A few days afterwards, when not far distant from the Abrolhos Islets, my attention was called to a reddish-brown appearance in the sea. The whole surface of the water, as it appeared under a weak lens, seemed as if covered by chopped bits of hay, with their ends jagged. These are minute cylindrical confervae, in bundles or rafts of from twenty to sixty in each. Mr. Berkeley informs me that they are the same species (Trichodesmium erythraeum) with that found over large spaces in the Red Sea, and whence its name of Red Sea is derived. (1/8. M. Montagne in "Comptes Rendus" etc. Juillet 1844; and "Annales des Sciences Naturelles" December 1844.) Their numbers must be infinite: the ship passed through several bands of them, one of which was about ten yards wide, and, judging from the mud-like colour of the water, at least two and a half miles long. In almost every long voyage some account is given of these confervae. They appear especially common in the sea near Australia; and off Cape Leeuwin I found an allied, but smaller and apparently different species. Captain Cook, in his third voyage, remarks that the sailors gave to this appearance the name of sea-sawdust.

Near Keeling Atoll, in the Indian Ocean, I observed many little masses of confervae a few inches square, consisting of long cylindrical threads of excessive thinness, so as to be barely visible to the naked eye, mingled with other rather larger bodies, finely conical at both ends. Two of these are shown in Plate 6 united together. They vary in length from .04 to .06, and even to .08 of an inch in length; and in diameter from .006 to .008 of an inch. Near one extremity of the cylindrical part, a green septum, formed of granular matter, and thickest in the middle, may generally be seen. This, I believe, is the bottom of a most delicate, colourless sac, composed of a pulpy substance, which lines the exterior case, but does not extend within the extreme conical points. In some specimens, small but perfect spheres of brownish granular matter supplied the places of the septa; and I observed the curious process by which they were produced. The pulpy matter of the internal coating suddenly grouped itself into lines, some of which assumed a form radiating from a common centre; it then continued, with an irregular and rapid movement, to contract itself, so that in the course of a second the whole was united into a perfect little sphere, which occupied the position of the septum at one end of the now quite hollow case. The formation of the granular sphere was hastened by any accidental injury. I may add, that frequently a pair of these bodies were attached to each other, as represented above, cone beside cone, at that end where the septum occurs.

I will here add a few other observations connected with the discoloration of the sea from organic causes. On the coast of Chile, a few leagues north of Concepcion, the "Beagle" one day passed through great bands of muddy water, exactly like that of a swollen river; and again, a degree south of Valparaiso, when fifty miles from the land, the same appearance was still more extensive. Some of the water placed in a glass was of a pale reddish tint; and, examined under a microscope, was seen to swarm with minute animalcula darting about, and often exploding. Their shape is oval, and contracted in the middle by a ring of vibrating curved ciliae. It was, however, very difficult to examine them with care, for almost the instant motion ceased, even while crossing the field of vision, their bodies burst. Sometimes both ends burst at once, sometimes only one, and a quantity of coarse, brownish, granular matter was ejected. The animal an instant before bursting expanded to half again its natural size; and the explosion took place about fifteen seconds after the rapid progressive motion had ceased: in a few cases it was preceded for a short interval by a rotatory movement on the longer axis. About two minutes after any number were isolated in a drop of water, they thus perished. The animals move with the narrow apex forwards, by the aid of their vibratory ciliae, and generally by rapid starts. They are exceedingly minute, and quite invisible to the naked eye, only covering a space equal to the square of the thousandth of an inch. Their numbers were infinite; for the smallest drop of water which I could remove contained very many. In one day we passed through two spaces of water thus stained, one of which alone must have extended over several square miles. What incalculable numbers of these microscopical animals! The colour of the water, as seen at some distance, was like that of a river which has flowed through a red clay district; but under the shade of the vessel's side it was quite as dark as chocolate. The line where the red and blue water joined was distinctly defined. The weather for some days previously had been calm, and the ocean abounded, to an unusual degree, with living creatures. (1/9. M. Lesson "Voyage de la Coquille" tome 1 page 255, mentions red water off Lima, apparently produced by the same cause. Peron, the distinguished naturalist, in the "Voyage aux Terres Australes," gives no less than twelve references to voyagers who have alluded to the discoloured waters of the sea (volume 2 page 239). To the references given by Peron may be added, Humboldt's "Personal Narrative" volume 6 page 804; Flinder's "Voyage" volume 1 page 92; Labillardiere, volume 1 page 287; Ulloa's "Voyage"; "Voyage of the Astrolabe and of the Coquille"; Captain King's "Survey of Australia" etc.)

In the sea around Tierra del Fuego, and at no great distance from the land, I have seen narrow lines of water of a bright red colour, from the number of crustacea, which somewhat resemble in form large prawns. The sealers call them whale-food. Whether whales feed on them I do not know; but terns, cormorants, and immense herds of great unwieldy seals derive, on some parts of the coast, their chief sustenance from these swimming crabs. Seamen invariably attribute the discoloration of the water to spawn; but I found this to be the case only on one occasion. At the distance of several leagues from the Archipelago of the Galapagos, the ship sailed through three strips of a dark yellowish, or mud-like water; these strips were some miles long, but only a few yards wide, and they were separated from the surrounding water by a sinuous yet distinct margin. The colour was caused by little gelatinous balls, about the fifth of an inch in diameter, in which numerous minute spherical ovules were embedded: they were of two distinct kinds, one being of a reddish colour and of a different shape from the other. I cannot form a conjecture as to what two kinds of animals these belonged. Captain Colnett remarks that this appearance is very common among the Galapagos Islands, and that the direction of the bands indicates that of the currents; in the described case, however, the line was caused by the wind. The only other appearance which I have to notice, is a thin oily coat on the water which displays iridescent colours. I saw a considerable tract of the ocean thus covered on the coast of Brazil; the seamen attributed it to the putrefying carcass of some whale, which probably was floating at no great distance. I do not here mention the minute gelatinous particles, hereafter to be referred to, which are frequently dispersed throughout the water, for they are not sufficiently abundant to create any change of colour.

There are two circumstances in the above accounts which appear remarkable: first, how do the various bodies which form the bands with defined edges keep together? In the case of the prawn-like crabs, their movements were as coinstantaneous as in a regiment of soldiers; but this cannot happen from anything like voluntary action with the ovules, or the confervae, nor is it probable among the infusoria. Secondly, what causes the length and narrowness of the bands? The appearance so much resembles that which may be seen in every torrent, where the stream uncoils into long streaks the froth collected in the eddies, that I must attribute the effect to a similar action either of the currents of the air or sea. Under this supposition we must believe that the various organised bodies are produced in certain favourable places, and are thence removed by the set of either wind or water. I confess, however, there is a very great difficulty in imagining any one spot to be the birthplace of the millions of millions of animalcula and confervae: for whence come the germs at such points?—the parent bodies having been distributed by the winds and waves over the immense ocean. But on no other hypothesis can I understand their linear grouping. I may add that Scoresby remarks that green water abounding with pelagic animals is invariably found in a certain part of the Arctic Sea.

(PLATE 7. CATAMARAN (BAHIA).)



CHAPTER II.

(PLATE 8. BOTOFOGO BAY, RIO DE JANEIRO.)

Rio de Janeiro. Excursion north of Cape Frio. Great Evaporation. Slavery. Botofogo Bay. Terrestrial Planariae. Clouds on the Corcovado. Heavy Rain. Musical Frogs. Phosphorescent Insects. Elater, springing powers of. Blue Haze. Noise made by a Butterfly. Entomology. Ants. Wasp killing a Spider. Parasitical Spider. Artifices of an Epeira. Gregarious Spider. Spider with an unsymmetrical Web.

RIO DE JANEIRO.

APRIL 4 TO JULY 5, 1832.



A few days after our arrival I became acquainted with an Englishman who was going to visit his estate, situated rather more than a hundred miles from the capital, to the northward of Cape Frio. I gladly accepted his kind offer of allowing me to accompany him.

APRIL 8, 1832.

Our party amounted to seven. The first stage was very interesting. The day was powerfully hot, and as we passed through the woods, everything was motionless, excepting the large and brilliant butterflies, which lazily fluttered about. The view seen when crossing the hills behind Praia Grande was most beautiful; the colours were intense, and the prevailing tint a dark blue; the sky and the calm waters of the bay vied with each other in splendour. After passing through some cultivated country, we entered a forest which in the grandeur of all its parts could not be exceeded. We arrived by midday at Ithacaia; this small village is situated on a plain, and round the central house are the huts of the negroes. These, from their regular form and position, reminded me of the drawings of the Hottentot habitations in Southern Africa. As the moon rose early, we determined to start the same evening for our sleeping-place at the Lagoa Marica. As it was growing dark we passed under one of the massive, bare, and steep hills of granite which are so common in this country. This spot is notorious from having been, for a long time, the residence of some runaway slaves, who, by cultivating a little ground near the top, contrived to eke out a subsistence. At length they were discovered, and a party of soldiers being sent, the whole were seized with the exception of one old woman, who, sooner than again be led into slavery, dashed herself to pieces from the summit of the mountain. In a Roman matron this would have been called the noble love of freedom: in a poor negress it is mere brutal obstinacy. We continued riding for some hours. For the few last miles the road was intricate, and it passed through a desert waste of marshes and lagoons. The scene by the dimmed light of the moon was most desolate. A few fireflies flitted by us; and the solitary snipe, as it rose, uttered its plaintive cry. The distant and sullen roar of the sea scarcely broke the stillness of the night.

APRIL 9, 1832.

We left our miserable sleeping-place before sunrise. The road passed through a narrow sandy plain, lying between the sea and the interior salt lagoons. The number of beautiful fishing birds, such as egrets and cranes, and the succulent plants assuming most fantastical forms, gave to the scene an interest which it would not otherwise have possessed. The few stunted trees were loaded with parasitical plants, among which the beauty and delicious fragrance of some of the orchideae were most to be admired. As the sun rose, the day became extremely hot, and the reflection of the light and heat from the white sand was very distressing. We dined at Mandetiba; the thermometer in the shade being 84 degrees. The beautiful view of the distant wooded hills, reflected in the perfectly calm water of an extensive lagoon, quite refreshed us. As the venda here was a very good one, and I have the pleasant, but rare remembrance, of an excellent dinner, I will be grateful and presently describe it, as the type of its class. (2/1. Venda, the Portuguese name for an inn.) These houses are often large, and are built of thick upright posts, with boughs interwoven, and afterwards plastered. They seldom have floors, and never glazed windows; but are generally pretty well roofed. Universally the front part is open, forming a kind of verandah, in which tables and benches are placed. The bedrooms join on each side, and here the passenger may sleep as comfortably as he can, on a wooden platform covered by a thin straw mat. The venda stands in a courtyard, where the horses are fed. On first arriving, it was our custom to unsaddle the horses and give them their Indian corn; then, with a low bow, to ask the senhor to do us the favour to give us something to eat. "Anything you choose, sir," was his usual answer. For the few first times, vainly I thanked providence for having guided us to so good a man. The conversation proceeding, the case universally became deplorable. "Any fish can you do us the favour of giving ?"—"Oh no, sir."—"Any soup?"—"No, sir."—"Any bread?"—"Oh no, sir."—"Any dried meat?"—"Oh no, sir." If we were lucky, by waiting a couple of hours, we obtained fowls, rice, and farinha. It not unfrequently happened that we were obliged to kill, with stones, the poultry for our own supper. When, thoroughly exhausted by fatigue and hunger, we timorously hinted that we should be glad of our meal, the pompous, and (though true) most unsatisfactory answer was, "It will be ready when it is ready." If we had dared to remonstrate any further, we should have been told to proceed on our journey, as being too impertinent. The hosts are most ungracious and disagreeable in their manners; their houses and their persons are often filthily dirty; the want of the accommodation of forks, knives, and spoons is common; and I am sure no cottage or hovel in England could be found in a state so utterly destitute of every comfort. At Campos Novos, however, we fared sumptuously; having rice and fowls, biscuit, wine, and spirits, for dinner; coffee in the evening, and fish with coffee for breakfast. All this, with good food for the horses, only cost 2 shillings 6 pence per head. Yet the host of this venda, being asked if he knew anything of a whip which one of the party had lost, gruffly answered, "How should I know? why did you not take care of it?—I suppose the dogs have eaten it."

Leaving Mandetiba, we continued to pass through an intricate wilderness of lakes; in some of which were fresh, in others salt water shells. Of the former kind, I found a Limnaea in great numbers in a lake, into which the inhabitants assured me that the sea enters once a year, and sometimes oftener, and makes the water quite salt. I have no doubt many interesting facts in relation to marine and fresh-water animals might be observed in this chain of lagoons which skirt the coast of Brazil. M. Gay has stated that he found in the neighbourhood of Rio shells of the marine genera solen and mytilus, and fresh-water ampullariae, living together in brackish water. (2/2. "Annales des Sciences Naturelles" for 1833.) I also frequently observed in the lagoon near the Botanic Garden, where the water is only a little less salt than in the sea, a species of hydrophilus, very similar to a water-beetle common in the ditches of England: in the same lake the only shell belonged to a genus generally found in estuaries.

(PLATE 9. VAMPIRE BAT (Desmodus D'Orbigny). Caught on back of Darwin's horse near Coquimbo. Head, full size.)

Leaving the coast for a time, we again entered the forest. The trees were very lofty, and remarkable, compared with those of Europe, from the whiteness of their trunks. I see by my notebook, "wonderful and beautiful flowering parasites," invariably struck me as the most novel object in these grand scenes. Travelling onwards we passed through tracts of pasturage, much injured by the enormous conical ants' nests, which were nearly twelve feet high. They gave to the plain exactly the appearance of the mud volcanoes at Jorullo, as figured by Humboldt. We arrived at Engenhodo after it was dark, having been ten hours on horseback. I never ceased, during the whole journey, to be surprised at the amount of labour which the horses were capable of enduring; they appeared also to recover from any injury much sooner than those of our English breed. The Vampire bat is often the cause of much trouble, by biting the horses on their withers. The injury is generally not so much owing to the loss of blood, as to the inflammation which the pressure of the saddle afterwards produces. The whole circumstance has lately been doubted in England; I was therefore fortunate in being present when one (Desmodus d'orbignyi, Wat.) was actually caught on a horse's back. We were bivouacking late one evening near Coquimbo, in Chile, when my servant, noticing that one of the horses was very restive, went to see what was the matter, and fancying he could distinguish something, suddenly put his hand on the beast's withers, and secured the vampire. In the morning the spot where the bite had been inflicted was easily distinguished from being slightly swollen and bloody. The third day afterwards we rode the horse, without any ill effects.

APRIL 13, 1832.

After three days' travelling we arrived at Socego, the estate of Senhor Manuel Figuireda, a relation of one of our party. The house was simple, and, though like a barn in form, was well suited to the climate. In the sitting-room gilded chairs and sofas were oddly contrasted with the whitewashed walls, thatched roof, and windows without glass. The house, together with the granaries, the stables, and workshops for the blacks, who had been taught various trades, formed a rude kind of quadrangle; in the centre of which a large pile of coffee was drying. These buildings stand on a little hill, overlooking the cultivated ground, and surrounded on every side by a wall of dark green luxuriant forest. The chief produce of this part of the country is coffee. Each tree is supposed to yield annually, on an average, two pounds; but some give as much as eight. Mandioca or cassava is likewise cultivated in great quantity. Every part of this plant is useful: the leaves and stalks are eaten by the horses, and the roots are ground into a pulp, which, when pressed dry and baked, forms the farinha, the principal article of sustenance in the Brazils. It is a curious, though well-known fact, that the juice of this most nutritious plant is highly poisonous. A few years ago a cow died at this Fazenda, in consequence of having drunk some of it. Senhor Figuireda told me that he had planted, the year before, one bag of feijao or beans, and three of rice; the former of which produced eighty, and the latter three hundred and twenty fold. The pasturage supports a fine stock of cattle, and the woods are so full of game that a deer had been killed on each of the three previous days. This profusion of food showed itself at dinner, where, if the tables did not groan, the guests surely did; for each person is expected to eat of every dish. One day, having, as I thought, nicely calculated so that nothing should go away untasted, to my utter dismay a roast turkey and a pig appeared in all their substantial reality. During the meals, it was the employment of a man to drive out of the room sundry old hounds, and dozens of little black children, which crawled in together, at every opportunity. As long as the idea of slavery could be banished, there was something exceedingly fascinating in this simple and patriarchal style of living: it was such a perfect retirement and independence from the rest of the world. As soon as any stranger is seen arriving, a large bell is set tolling, and generally some small cannon are fired. The event is thus announced to the rocks and woods, but to nothing else. One morning I walked out an hour before daylight to admire the solemn stillness of the scene; at last, the silence was broken by the morning hymn, raised on high by the whole body of the blacks; and in this manner their daily work is generally begun. On such fazendas as these, I have no doubt the slaves pass happy and contented lives. On Saturday and Sunday they work for themselves, and in this fertile climate the labour of two days is sufficient to support a man and his family for the whole week.

APRIL 14, 1832.

(PLATE 10. VIRGIN FOREST.)

Leaving Soc^go, we rode to another estate on the Rio Macfe, which was the last patch of cultivated ground in that direction. The estate was two and a half miles long, and the owner had forgotten how many broad. Only a very small piece had been cleared, yet almost every acre was capable of yielding all the various rich productions of a tropical land. Considering the enormous area of Brazil, the proportion of cultivated ground can scarcely be considered as anything compared to that which is left in the state of nature: at some future age, how vast a population it will support! During the second day's journey we found the road so shut up that it was necessary that a man should go ahead with a sword to cut away the creepers. The forest abounded with beautiful objects; among which the tree ferns, though not large, were, from their bright green foliage, and the elegant curvature of their fronds, most worthy of admiration. In the evening it rained very heavily, and although the thermometer stood at 65 degrees, I felt very cold. As soon as the rain ceased, it was curious to observe the extraordinary evaporation which commenced over the whole extent of the forest. At the height of a hundred feet the hills were buried in a dense white vapour, which rose like columns of smoke from the most thickly-wooded parts, and especially from the valleys. I observed this phenomenon on several occasions: I suppose it is owing to the large surface of foliage, previously heated by the sun's rays.

While staying at this estate, I was very nearly being an eye-witness to one of those atrocious acts which can only take place in a slave country. Owing to a quarrel and a lawsuit, the owner was on the point of taking all the women and children from the male slaves, and selling them separately at the public auction at Rio. Interest, and not any feeling of compassion, prevented this act. Indeed, I do not believe the inhumanity of separating thirty families, who had lived together for many years, even occurred to the owner. Yet I will pledge myself, that in humanity and good feeling he was superior to the common run of men. It may be said there exists no limit to the blindness of interest and selfish habit. I may mention one very trifling anecdote, which at the time struck me more forcibly than any story of cruelty. I was crossing a ferry with a negro who was uncommonly stupid. In endeavouring to make him understand, I talked loud, and made signs, in doing which I passed my hand near his face. He, I suppose, thought I was in a passion, and was going to strike him; for instantly, with a frightened look and half-shut eyes, he dropped his hands. I shall never forget my feelings of surprise, disgust, and shame, at seeing a great powerful man afraid even to ward off a blow, directed, as he thought, at his face. This man had been trained to a degradation lower than the slavery of the most helpless animal.

APRIL 18, 1832.

(PLATE 11. CABBAGE PALM.)

In returning we spent two days at Soc^go, and I employed them in collecting insects in the forest. The greater number of trees, although so lofty, are not more than three or four feet in circumference. There are, of course, a few of much greater dimension. Senhor Manuel was then making a canoe 70 feet in length from a solid trunk, which had originally been 110 feet long, and of great thickness. The contrast of palm trees, growing amidst the common branching kinds, never fails to give the scene an intertropical character. Here the woods were ornamented by the Cabbage Palm—one of the most beautiful of its family. With a stem so narrow that it might be clasped with the two hands, it waves its elegant head at the height of forty or fifty feet above the ground. The woody creepers, themselves covered by other creepers, were of great thickness: some which I measured were two feet in circumference. Many of the older trees presented a very curious appearance from the tresses of a liana hanging from their boughs, and resembling bundles of hay. If the eye was turned from the world of foliage above, to the ground beneath, it was attracted by the extreme elegance of the leaves of the ferns and mimosae. The latter, in some parts, covered the surface with a brushwood only a few inches high. In walking across these thick beds of mimosae, a broad track was marked by the change of shade, produced by the drooping of their sensitive petioles. It is easy to specify the individual objects of admiration in these grand scenes; but it is not possible to give an adequate idea of the higher feelings of wonder, astonishment, and devotion, which fill and elevate the mind.

(PLATE 12. MANDIOCA OR CASSAVA.)

APRIL 19, 1832.

Leaving Soc^go, during the two first days we retraced our steps. It was very wearisome work, as the road generally ran across a glaring hot sandy plain, not far from the coast. I noticed that each time the horse put its foot on the fine siliceous sand, a gentle chirping noise was produced. On the third day we took a different line, and passed through the gay little village of Madre de De"s. This is one of the principal lines of road in Brazil; yet it was in so bad a state that no wheel vehicle, excepting the clumsy bullock-wagon, could pass along. In our whole journey we did not cross a single bridge built of stone; and those made of logs of wood were frequently so much out of repair that it was necessary to go on one side to avoid them. All distances are inaccurately known. The road is often marked by crosses, in the place of milestones, to signify where human blood has been spilled. On the evening of the 23rd we arrived at Rio, having finished our pleasant little excursion.

During the remainder of my stay at Rio, I resided in a cottage at Botofogo Bay. It was impossible to wish for anything more delightful than thus to spend some weeks in so magnificent a country. In England any person fond of natural history enjoys in his walks a great advantage, by always having something to attract his attention; but in these fertile climates, teeming with life, the attractions are so numerous, that he is scarcely able to walk at all.

The few observations which I was enabled to make were almost exclusively confined to the invertebrate animals. The existence of a division of the genus Planaria, which inhabits the dry land, interested me much. These animals are of so simple a structure, that Cuvier has arranged them with the intestinal worms, though never found within the bodies of other animals. Numerous species inhabit both salt and fresh water; but those to which I allude were found, even in the drier parts of the forest, beneath logs of rotten wood, on which I believe they feed. In general form they resemble little slugs, but are very much narrower in proportion, and several of the species are beautifully coloured with longitudinal stripes. Their structure is very simple: near the middle of the under or crawling surface there are two small transverse slits, from the anterior one of which a funnel-shaped and highly irritable mouth can be protruded. For some time after the rest of the animal was completely dead from the effects of salt water or any other cause, this organ still retained its vitality.

I found no less than twelve different species of terrestrial Planariae in different parts of the southern hemisphere. (2/3. I have described and named these species in the "Annals of Natural History" volume 14 page 241.) Some specimens which I obtained at Van Dieman's Land, I kept alive for nearly two months, feeding them on rotten wood. Having cut one of them transversely into two nearly equal parts, in the course of a fortnight both had the shape of perfect animals. I had, however, so divided the body, that one of the halves contained both the inferior orifices, and the other, in consequence, none. In the course of twenty-five days from the operation, the more perfect half could not have been distinguished from any other specimen. The other had increased much in size; and towards its posterior end, a clear space was formed in the parenchymatous mass, in which a rudimentary cup-shaped mouth could clearly be distinguished; on the under surface, however, no corresponding slit was yet open. If the increased heat of the weather, as we approached the equator, had not destroyed all the individuals, there can be no doubt that this last step would have completed its structure. Although so well known an experiment, it was interesting to watch the gradual production of every essential organ, out of the simple extremity of another animal. It is extremely difficult to preserve these Planariae; as soon as the cessation of life allows the ordinary laws of change to act, their entire bodies become soft and fluid, with a rapidity which I have never seen equalled.

I first visited the forest in which these Planariae were found, in company with an old Portuguese priest who took me out to hunt with him. The sport consisted in turning into the cover a few dogs, and then patiently waiting to fire at any animal which might appear. We were accompanied by the son of a neighbouring farmer—a good specimen of a wild Brazilian youth. He was dressed in a tattered old shirt and trousers, and had his head uncovered: he carried an old-fashioned gun and a large knife. The habit of carrying the knife is universal; and in traversing a thick wood it is almost necessary, on account of the creeping plants. The frequent occurrence of murder may be partly attributed to this habit. The Brazilians are so dexterous with the knife that they can throw it to some distance with precision, and with sufficient force to cause a fatal wound. I have seen a number of little boys practising this art as a game of play, and from their skill in hitting an upright stick, they promised well for more earnest attempts. My companion, the day before, had shot two large bearded monkeys. These animals have prehensile tails, the extremity of which, even after death, can support the whole weight of the body. One of them thus remained fast to a branch, and it was necessary to cut down a large tree to procure it. This was soon effected, and down came tree and monkey with an awful crash. Our day's sport, besides the monkey, was confined to sundry small green parrots and a few toucans. I profited, however, by my acquaintance with the Portuguese padre, for on another occasion he gave me a fine specimen of the Yagouaroundi cat.

Every one has heard of the beauty of the scenery near Botofogo. The house in which I lived was seated close beneath the well-known mountain of the Corcovado. It has been remarked, with much truth, that abruptly conical hills are characteristic of the formation which Humboldt designates as gneiss-granite. Nothing can be more striking than the effect of these huge rounded masses of naked rock rising out of the most luxuriant vegetation.

I was often interested by watching the clouds, which, rolling in from seaward, formed a bank just beneath the highest point of the Corcovado. This mountain, like most others, when thus partly veiled, appeared to rise to a far prouder elevation than its real height of 2300 feet. Mr. Daniell has observed, in his meteorological essays, that a cloud sometimes appears fixed on a mountain summit, while the wind continues to blow over it. The same phenomenon here presented a slightly different appearance. In this case the cloud was clearly seen to curl over, and rapidly pass by the summit, and yet was neither diminished nor increased in size. The sun was setting, and a gentle southerly breeze, striking against the southern side of the rock, mingled its current with the colder air above; and the vapour was thus condensed: but as the light wreaths of cloud passed over the ridge, and came within the influence of the warmer atmosphere of the northern sloping bank, they were immediately redissolved.

The climate, during the months of May and June, or the beginning of winter, was delightful. The mean temperature, from observations taken at nine o'clock, both morning and evening, was only 72 degrees. It often rained heavily, but the drying southerly winds soon again rendered the walks pleasant. One morning, in the course of six hours, 1.6 inches of rain fell. As this storm passed over the forests which surround the Corcovado, the sound produced by the drops pattering on the countless multitude of leaves was very remarkable, it could be heard at the distance of a quarter of a mile, and was like the rushing of a great body of water. After the hotter days, it was delicious to sit quietly in the garden and watch the evening pass into night. Nature, in these climes, chooses her vocalists from more humble performers than in Europe. A small frog, of the genus Hyla, sits on a blade of grass about an inch above the surface of the water, and sends forth a pleasing chirp: when several are together they sing in harmony on different notes. I had some difficulty in catching a specimen of this frog. The genus Hyla has its toes terminated by small suckers; and I found this animal could crawl up a pane of glass, when placed absolutely perpendicular. Various cicadae and crickets, at the same time, keep up a ceaseless shrill cry, but which, softened by the distance, is not unpleasant. Every evening after dark this great concert commenced; and often have I sat listening to it, until my attention has been drawn away by some curious passing insect.

At these times the fireflies are seen flitting about from hedge to hedge. On a dark night the light can be seen at about two hundred paces distant. It is remarkable that in all the different kinds of glowworms, shining elaters, and various marine animals (such as the crustacea, medusae, nereidae, a coralline of the genus Clytia, and Pyrosoma), which I have observed, the light has been of a well-marked green colour. All the fireflies, which I caught here, belonged to the Lampyridae (in which family the English glowworm is included), and the greater number of specimens were of Lampyris occidentalis. (2/4. I am greatly indebted to Mr. Waterhouse for his kindness in naming for me this and many other insects, and giving me much valuable assistance.) I found that this insect emitted the most brilliant flashes when irritated: in the intervals, the abdominal rings were obscured. The flash was almost coinstantaneous in the two rings, but it was just perceptible first in the anterior one. The shining matter was fluid and very adhesive: little spots, where the skin had been torn, continued bright with a slight scintillation, whilst the uninjured parts were obscured. When the insect was decapitated the rings remained uninterruptedly bright, but not so brilliant as before: local irritation with a needle always increased the vividness of the light. The rings in one instance retained their luminous property nearly twenty-four hours after the death of the insect. From these facts it would appear probable, that the animal has only the power of concealing or extinguishing the light for short intervals, and that at other times the display is involuntary. On the muddy and wet gravel-walks I found the larvae of this lampyris in great numbers: they resembled in general form the female of the English glowworm. These larvae possessed but feeble luminous powers; very differently from their parents, on the slightest touch they feigned death, and ceased to shine; nor did irritation excite any fresh display. I kept several of them alive for some time: their tails are very singular organs, for they act, by a well-fitted contrivance, as suckers or organs of attachment, and likewise as reservoirs for saliva, or some such fluid. I repeatedly fed them on raw meat; and I invariably observed, that every now and then the extremity of the tail was applied to the mouth, and a drop of fluid exuded on the meat, which was then in the act of being consumed. The tail, notwithstanding so much practice, does not seem to be able to find its way to the mouth; at least the neck was always touched first, and apparently as a guide.

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