394 



NATURE 



\_August 21, 1879 



But Buffon deliberately rejected the Linnjean classification — a 

 grave error, certainly, yet one not altogether without excuse. 

 Indeed, some of the objections he brought against that classifi- 

 cation have considerable force. Such were his objections to the 

 association of the hippopotamus, the shrew-mouse, and the horse 

 in one order, and of the monkey and the manis in another.^ 

 What indeed could be more preposterous than the separation 

 of the bat, NoctiUo leporinus, from the other bats, and its 

 association with the rodents, on the ground of its having (as 

 supposed) only two incisor teeth above and two below ? — an 

 anomaly of arrangement of which you were reminded last year. 

 It scarcely seems possible for the pedantry of classification to go 

 farther than this. Yet, perhaps, the association in one group of 

 tlie walrus, the elephant, the ant-eater, the sloth, and the mana- 

 tee, was hardly less unphilosophical. Moreover, zoologists should 

 not forget, in blaming Buffon for his want of appreciation of 

 the classification of Linnxus, that one great portion of that 

 classification — the classification of plants — has been superseded 

 by us. Had he lived to witness the publication of Jussieu's 

 "Genera Plantarum,"^ it might have given him a truer insight 

 into biological classification, and have led him to endeavour to 

 improve on Linnseus' system instead of only criticising it. 



But it is Buffon's speculative views which have most interest 

 for us. Those views exercised a very wide-spread influence in 

 their day, though the time was not ripe for them. Indeed, it is 

 far from improbable that writers whose speculations have been 

 made public at a more propitious season, owe much to their 

 comparatively forgotten predecessor. 



Amongst Buffon's various speculations we might glance at his 

 " Theorie de la Terre " (put forth in the very first volume of his 

 work), and at his "Epoques de la Nature," which fills the fifth 

 volume of his supplement. We might consider his speculations 

 concerning the formation of mountain and valley by water, and 

 the evidence that there was present to the ear of his imagina- 

 tion : — 



" The sound of streams, which, swift or slow, 

 Tear dow n ^Eolian hills and sow 

 The dust of continents to be.'* 



That he saw, in thought, the projection of the planets from the 

 sun's mass ; the primitive fluidity of the earth, and the secular 

 refrigeration of the sun. Such considerations, however, are 

 foreign to this section. I will therefore select two which are of 

 biological interest. 



In the first place I may refer to Buffon's speculations concern- 

 ing ANIMAL VARIATION. In this matter Isidore Geoffroy St. 

 Hilaire has affirmed that Bufibn stands to the doctrine of animal 

 variability in a position analogous to that in which Linnasus 

 stands to the doctrine of the fixity of species. 



Buffon, in his chapter on the animals of the Old and New 

 World, remarks,^ "It is not impossible that the whole* of 

 the new world's animals are derived from the same source 

 as those of the old, whence they have descended." .... 

 " Nature is in a state of perpetual flux." In this chapter on the 

 degeneration of animals ' he sums up saying, " After comparing 

 all the animals, and arranging them each in their own group, we 

 shall find that the two hundred kinds described here may be 

 reduced to a small number of original forms, whence it may be 

 all the rest have issued." 



As to the modes and causes of the origin of new forms, he 

 entertained four connected opinions : 



(1) He attributed much modifying efficacy to migrations ; 



(2) Also to the direct action of external conditions ; 



(3) He believed largely in the origin of new forms by 

 degradation ; and 



(4) He regarded each animal as the manifestation of an 

 individuating force, living, as it were, at the root of the changes 

 manifested by it. 



The view that migration (with isolation) is a necessary 

 antecedent to the origin of new species i? one which has been 

 advocated by a modern naturalist, Moritz Wagner ; " who does 

 not hesitate to affirm'' that the formation of a nearly new 



^ " Hist. -Nat." tome i. p. 39. 2 Xhis appeared in 1789. 



3 Op. cit. vol. ix. p. 127. 



4 He thought that the American Jaguars, Ocelots, &c., and even the 

 .Peccary, were positive degradations of old world forms. He thought that the 



Llama, the American Apes, Agoutis, and Ant-eaters might be examples of 

 such forms ; but the Opossum, Sloths, and Tapirs he took to be original 

 species. (See vol. xiv. pp. 272, 273.) 



5 Vol. xiv. p. 358. 



6 In a paper read before the Royal Academy of Sciences at Munich on 

 March 2, 1868. This has been translated by Mr. James L. Laird, and 

 fubUshed by Edward Stanford in 1S73. 



^ Op. cit, p. 29. 



species " will only succeed when a few individuals, having 

 crossed the barriers of their station, are able to separate them- 

 selves for a long time from the old stock." 



In support of his view the author brings forward a multitude 

 of interesting facts, one of the most significant of which appears 

 to me to be the following. It concerns Beetles of Tropical 

 America of the genus Tdracha. In Venezuela, and in the 

 western part of Central America, he tells us rivers flow partly 

 through savannah's, where they have undermined the light 

 tufaceous soil, forming deep beds with high precipitous ^banks. 

 According to Prof. Wagner, individual beetles from the high- 

 lands have thus been isolated, and in no longer time than has 

 been required by the rivers to undermine the loose soil of the 

 savannah, have given rise to a distinct species markedly different 

 in form and colour. It is to similar causes — migration and com- 

 plete isolation — that he traces the formation of distinct races ot 

 men : a formation he deems no longer possible, while the wide 

 diffusion of mankind renders more and more difficult the 

 evolution of new species of animals of any kind. 



Instances which appear to support this view will readily 

 suggest themselves to the naturalist — instances, that is, of forms 

 which are both peculiar in structure and remote and isolated as 

 to their^habitat.i Thus for example, even in the group which 

 structurally most resembles us, we have the Orang confined to 

 very limited tracts in Borneo and Sumatra, and the G orilla to a 

 small portion of Western Africa. The Proboscis Monkey'jis found 

 nowhere but in Borneo, while the singular ape named " Roxel- 

 lana," (from its wonderfully " tip-tilted" nose) is confined to the 

 lofty and isolated mountains of Monpin in Thibet. The very 

 peculiar black ape {Cynopithecus) is limited to Celebes and 

 Batchian, while the Baboon, which has the baboon character 

 of muzzle most developed, was found at the extreme south of 

 the African continent. 



Again, if we t.ake the group of Lemur-like animals (Lemu- 

 roidea) as having had their home and starting-point in or near 

 their present head-quarters — Madagascar — then some of the 

 most aberrant forms are those which must have migrated farthest. 

 The character which is perhaps the most peculiar of any which 

 the group presents, is the elongation of two of the ankle-bones, 

 as we find it in the Madagascar genus Cheirogalms. But this 

 character is more exaggerated in migrants to Africa — the ^M 

 Galagos — and most so of all in the more isolated emigrant, the :^B 

 Tarsier, now found in Celebes and Borneo. 



The sub-family of slow-lemurs (Nycticebinis) would, on this 

 view, seemed to have migrated in opposite directions, as we find 

 the slender slow-lemur [Loris) in Madras, Malabar, and Ceylon ; 

 the typical slow-lemur {Nyciicebzis) in South China, Borneo, and 

 Java ; the Potto (Perodicticus) in Sierra Leone, and the Ang- 

 wantibo (Aictocel/us) in Old Calabar. Of these, it is the African 

 forms which have the index-finger mo.it atrophied — a tendency 

 to its atrophy existing in the whole sub-family. 



It would, of course, be very easy to multiply instances of the 

 kind ; but it would be also easy to cite a number of cases which 

 appear to conflict with the view in question. Thus familiar to 

 us as it is, few animals are more peculiar in structure than the 

 common mole, which gives no present evidence of isolated origin; 

 and the most aberrant of all bats, the Vampire {Dismodus), is 

 rather widely distributed in South America. Again, with regard 

 to the Lemur group, the most absolutely exceptional is the 

 Aye- Aye {Chciromys), which, on the hypothesis supposed, has 

 remained persistently at the head-quarters of the group, i.e. in 

 Madagascar. 



Even, however, if no exception existed to the co-existence 

 now of singularity of form and isolation and remoteness of 

 situation, we could not safely draw any decided conclusion 

 from such facts, because fossil remains show us that forms 

 which have now a very limited distribution, were either widely 

 spread in earlier times, or existed in regions very remote from 

 those they now inhabit. Thus, in Eocene times ithere existed in 

 Europe true opossums (now confined to America), Tapirs, and 

 a form like the African Potto before mentioned. In Miocene 

 times we had in Europe long-armed apes (creatures now found 

 only in Eastern Asia), with the'now exclusively African Secretary 

 Bird and Cape Ant Eater (Orycteropis). In the same period the 

 Orang— or a nearly aUied form— seems to have ranged over 



' Isolation, it ought to be remembered, may take place as the result not 

 only of changes in inorganic nature (such as the formation of islands, and 

 the excavation of river beds), but also by the presence of enemies m inter- 

 medi.-ite tracts, by the circumstance that the food of the species is found 

 only in certain restricted localities, and by whatever other causes determine 

 the extinction of a species in a given place. 



