An Appreciation

BY CHARLES DARWIN Author of "The Origin of Species," etc.

From Natural History Review, vol. iii. 1863.

IN April, 1848, the author of the present volume left England in company with Mr. A. R. Wallace—"who has since acquired wide fame in connection with the Darwinian theory of Natural Selection"—on a joint expedition up the river Amazons, for the purpose of investigating the Natural History of the vast wood-region traversed by that mighty river and its numerous tributaries. Mr. Wallace returned to England after four years’ stay, and was, we believe, unlucky enough to lose the greater part of his collections by the shipwreck of the vessel in which he had transmitted them to London. Mr. Bates prolonged his residence in the Amazon valley seven years after Mr. Wallace’s departure, and did not revisit his native country again until 1859. Mr. Bates was also more fortunate than his companion in bringing his gathered treasures home to England in safety. So great, indeed, was the mass of specimens accumulated by Mr. Bates during his eleven years’ researches, that upon the working out of his collection, which has been accomplished (or is now in course of being accomplished) by different scientific naturalists in this country, it has been ascertained that representatives of no less than 14,712 species are amongst them, of which about 8000 were previously unknown to science. It may be remarked that by far the greater portion of these species, namely, about 14,000, belong to the class of Insects—to the study of which Mr. Bates principally devoted his attention—being, as is well known, himself recognised as no mean authority as regards this class of organic beings. In his present volume, however, Mr. Bates does not confine himself to his entomological discoveries, nor to any other branch of Natural History, but supplies a general outline of his adventures during his journeyings up and down the mighty river, and a variety of information concerning every object of interest, whether physical or political, that he met with by the way.

Mr. Bates landed at Para in May, 1848. His first part is entirely taken up with an account of the Lower Amazons—that is, the river from its sources up to the city of Manaos or Barra do Rio Negro, where it is joined by the large northern confluent of that name— and with a narrative of his residence at Para and his various excursions in the neighbourhood of that city. The large collection made by Mr. Bates of the animal productions of Para enabled him to arrive at the following conclusions regarding the relations of the Fauna of the south side of the Amazonian delta with those of other regions.

"It is generally allowed that Guiana and Brazil, to the north and south of the Para district, form two distinct provinces, as regards their animal and vegetable inhabitants. By this it means that the two regions have a very large number of forms peculiar to themselves, and which are supposed not to have been derived from other quarters during modern geological times. Each may be considered as a centre of distribution in the latest process of dissemination of species over the surface of tropical America. Para lies midway between the two centres, each of which has a nucleus of elevated table-land, whilst the intermediate rivervalley forms a wide extent of low-lying country. It is, therefore, interesting to ascertain from which the latter received its population, or whether it contains so large a number of endemic species as would warrant the conclusion that it is itself an independent province. To assist in deciding such questions as these, we must compare closely the species found in the district with those of the other contiguous regions, and endeavour to ascertain whether they are identical, or only slightly modified, or whether they are highly peculiar.

"Von Martius when he visited this part of Brazil forty years ago, coming from the south, was much struck with the dissimilarity of the animal and vegetable productions to those of other parts of Brazil. In fact the Fauna of Para, and the lower part of the Amazons has no close relationship with that of Brazil proper; but it has a very great affinity with that of the coast region of Guiana, from Cayenne to Demerara. If we may judge from the results afforded by the study of certain families of insects, no peculiar Brazilian forms are found in the Para district; whilst more than one-half of the total number are essentially Guiana species, being found nowhere else but in Guiana and Amazonia. Many of them, however, are modified from the Guiana type, and about one-seventh seem to be restricted to Para. These endemic species are not highly peculiar, and they may yet be found over a great part of Northern Brazil when the country is better explored. They do not warrant us in concluding that the district forms an independent province, although they show that its Fauna is not wholly derivative, and that the land is probably not entirely a new formation. From all these facts, I think we must conclude that the Para district belongs to the Guiana province and that, if it is newer land than Guiana, it must have received the great bulk of its animal population from that region. I am informed by Dr. Sclater that similar results are derivable from the comparison of the birds of these countries."

One of the most interesting excursions made by Mr. Bates from Para was the ascent of the river Tocantins—the mouth of which lies about 4-5 miles from the city of Para. This was twice attempted. On the second occasion—our author being in company with Mr. Wallace—the travellers penetrated as far as the rapids of Arroyos, about 130 miles from its mouth. This district is one of the chief collecting-grounds of the well-known Brazil-nut (Bertholletia excelsa), which is here very plentiful, grove after grove of these splendid trees being visible, towering above their fellows, with the "woody fruits, large and round as cannon-balls, dotted over the branches." The Hyacinthine Macaw (Ara hyacinthina) is another natural wonder, first met with here. This splendid bird, which is occasionally brought alive to the Zoological Gardens of Europe, "only occurs in the interior of Brazil, from 16’ S.L. to the southern border of the Amazon valley." Its enormous beak—which must strike even the most unobservant with wonder—appears to be adapted to enable it to feed on the nuts of the Mucuja Palm (Acrocomia lasiospatha). "These nuts, which are so hard as to be difficult to break with a heavy hammer, are crushed to a pulp by the powerful beak of this Macaw."

Mr. Bates’ later part is mainly devoted to his residence at Santarem, at the junction of the Rio Tapajos with the main stream, and to his account of Upper Amazon, or Solimoens—the Fauna of which is, as we shall presently see, in many respects very different from that of the lower part of the river. At Santarem—"the most important and most civilised settlement on the Amazon, between the Atlantic and Para "—Mr. Bates made his headquarters for three years and a half, during which time several excursions up the little-known Tapajos were effected. Some 70 miles up the stream, on its affluent, the Cupari, a new Fauna, for the most part very distinct from that of the lower part of the same stream, was entered upon. "At the same time a considerable proportion of the Cupari species were identical with those of Ega, on the Upper Amazon, a district eight times further removed than the village just mentioned." Mr. Bates was more successful here than on his excursion up the Tocantins, and obtained twenty new species of fishes, and many new and conspicuous insects, apparently peculiar to this part of the Amazonian valley.

In a later chapter Mr. Bates commences his account of the Solimoens, or Upper Amazons, on the banks of which he passed four years and a half. The country is a "magnificent wilderness, where civilised man has, as yet, scarcely obtained a footing-the cultivated ground, from the Rio Negro to the Andes, amounting only to a few score acres." During the whole of this time Mr. Bates’ headquarters were at Ega, on the Teffe, a confluent of the great river from the south, whence excursions were made sometimes for 300 or 400 miles into the interior. In the intervals Mr. Bates followed his pursuit as a collecting naturalist in the same "peaceful, regular way," as he might have done in a European village. Our author draws a most striking picture of the quiet, secluded life he led in this far-distant spot. The difficulty of getting news and the want of intellectual society were the great drawbacks—"the latter increasing until it became almost insupportable." "I was obliged at last," Mr. Bates naively remarks, "to come to the conclusion that the contemplation of Nature, alone is not sufficient to fill the human heart and mind." Mr. Bates must indeed have been driven to great straits as regards his mental food, when, as he tell us, he took to reading the Athenaeum three times over, "the first time devouring the more interesting articles—the second, the whole of the remainder—and the third, reading all the advertisements from beginning to end."

Ega was, indeed, as Mr. Bates remarks, a fine field for a Natural History collector, the only previous scientific visitants to that region having been the German Naturalists, Spix and Martius, and the Count de Castelnau when he descended the Amazons from the Pacific. Mr. Bates’ account of the monkeys of the genera Brachyuyus, Nyctipithecus and Midas met with in this region, and the whole of the very pregnant remarks which follow on the American forms of the Quadrumana, will be read with interest by every one, particularly by those who pay attention to the important subject of geographical distribution. We need hardly say that Mr. Bates, after the attention he has bestowed upon this question, is a zealous advocate of the hypothesis of the origin of species by derivation from a common stock. After giving an outline of the general distribution of Monkeys, he clearly argues that unless the "common origin at least of the species of a family be admitted, the problem of their distribution must remain an inexplicable mystery." Mr. Bates evidently thoroughly understands the nature of this interesting problem, and in another passage, in which the very singular distribution of the Butterflies of the genus Heliconius is enlarged upon, concludes with the following significant remarks upon this important subject:

"In the controversy which is being waged amongst Naturalists since the publication of the Darwinian theory of the origin of species, it has been rightly said that no proof at present existed of the production of a physiological species, that is, a form which will not interbreed with the one from which it was derived, although given ample opportunities of doing so, and does not exhibit signs of reverting to its parent form when placed under the same conditions with it. Morphological species, that is, forms which differ to an amount that would justify their being considered good species, have been produced in plenty through selection by man out of variations arising under domestication or cultivation. The facts just given are therefore of some scientific importance, for they tend to show that a physiological species can be and is produced in nature out of the varieties of a pre-existing closely allied one. This is not an isolated case, for I observed in the course of my travels a number of similar instances. But in very few has it happened that the species which clearly appears to be the parent, co-exists with one that has been evidently derived from it. Generally the supposed parent also seems to have been modified, and then the demonstration is not so clear, for some of the links in the chain of variation are wanting. The process of origination of a species in nature as it takes place successively, must be ever, perhaps, beyond man’s power to trace, on account of the great lapse of time it requires. But we can obtain a fair view of it by tracing a variable and far-spreading species over the wide area of its present distribution; and a long observation of such will lead to the conclusion that new species must in all cases have arisen out of variable and widely-disseminated forms. It sometimes happens, as in the present instance, that we find in one locality a species under a certain form which is constant to all the individuals concerned; in another exhibiting numerous varieties; and in a third presenting itself as a constant form quite distinct from the one we set out with. If we meet with any two of these modifications living side by side, and maintaining their distinctive characters under such circumstances, the proof of the natural origination of a species is complete; it could not be much more so were we able to watch the process step by step. It might be objected that the difference between our two species is but slight, and that by classing them as varieties nothing further would be proved by them. But the differences between them are such as obtain between allied species generally. Large genera are composed in great part of such species, and it is interesting to show the great and beautiful diversity within a large genus as brought about by the working of laws within our comprehension."

But to return to the Zoological wonders of the Upper Amazon, birds, insects, and butterflies are all spoken of by Mr. Bates in his chapter on the natural features of the district, and it is evident that none of these classes of beings escaped the observation of his watchful intelligence. The account of the foraging ants of the genus Eciton is certainly marvellous, and would, even of itself, be sufficient to stamp the recorder of their habits as a man of no ordinary mark.

The last chapter of Mr. Bates’ work contains the account of his excursions beyond Ega. Fonteboa, Tunantins—a small semi-Indian settlement, 240 miles up the stream—and San Paulo de Olivenca, some miles higher up, were the principal places visited, and new acquisitions were gathered at each of these localities. In the fourth month of Mr. Bates’ residence at the last-named place, a severe attack of ague led to the abandonment of the plans he had formed of proceeding to the Peruvian towns of Pebas and Moyobamba, and "so completing the examination of the Natural History of the Amazonian plains up to the foot of the Andes." This attack, which seemed to be the culmination of a gradual deterioration of health, caused by eleven years’ hard work under the tropics, induced him to return to Ega, and finally to Para, where he embarked, on the 2nd June 1859, for England. Naturally enough, Mr. Bates tells us he was at first a little dismayed at leaving the equator, "where the well-balanced forces of Nature maintain a land-surface and a climate typical of mind, and order and beauty," to sail towards the "crepuscular skies" of the cold north. But he consoles us by adding the remark that "three years’ renewed experience of England" have convinced him "how incomparably superior is civilised life to the spiritual sterility of half-savage existence, even if it were passed in the Garden of Eden."

The following is the list of H. W. Bates’ published works:

Contributions to an insect Fauna of the Amazon Valley, Paper read before the Linnean Society, June 21, 1861; The Naturalist on the Amazons, a Record of Adventure, Habits of Animals, Sketches of Brazilian and Indian Life . . . during Eleven Years of Travel, 1863; 3rd Edition, 1873, with a Memoir of the author by E. Clodd to reprint of unabridged edition, 1892.

Bates was for many years the editor of the Transactions of the Royal Geographical Society; the following works were edited and revised, or supplemented by him:—Mrs. Somerville’s Physical Geography, 1870; A. Humbert, Japan and the Japanese, 1874; C. Koldewey, the German Arctic Expedition, 1874; P. E. Warburton, Journey across the Western Interior of Australia, 1875; Cassell’s Illustrated Travels, 6 vols., 1869-1875; E. Whymper, Travels among the Great Andes of the Equator (Introduction to Appendix volume), 1892, etc.; Central America, the West Indies and South America; Stanford’s Compendium of Geography and Travel, 2nd revised Ed., 1882; he also added a list of Coleoptera collected by J. S. Jameson on the Aruwini to the latter’s Story of the Rear Column of the Emin Pasha Relief Expedition, etc., 1890; and an appendix to a catalogue of Phytophaga by H. Clark, 1866, etc.; and contributed a biographical notice of Keith Johnson to J. Thomson’s Central African Lakes and Back, 1881.

He contributed largely to the Zoologist, Entomological Society’s journal, Annals and Magazine of Natural History, and Entomologist.

LIFE—Memoir by E. Clodd, 1892; short notice in Clodd’s Pioneers of Evolution, 1897.