68 



KNOWLEDGE. 



[Mabch 1, 1895. 



NEW ANIMALS FROM MADAGASCAR. 



By E. Lyuekkee, B.A.Cantab., F.E.S. 



AT a time when public attention is directed to 

 Madagascar as the scene of an impending war, 

 our readers will doubtless be glad to hear 

 something of certain new discoveries which have 

 recently thrown much additional light on the 

 past zoological history of this most interesting and 

 remarkable island. Probably many of them are aware 

 that the Malagasy fauna difl'ers most strikingly from that 

 of the African mainland, in spite of the small extent of sea 

 by which the two areas are separated from one another ; 

 and it is evident that although the ancestors of the 

 majority of the animals now inhabiting Madagascar 

 obtained an entrance by means of a former land connection 

 with East Africa, yet the date of that connection must 

 have been extremely remote. At the present day, Africa 

 south of the Sahara desert is specially characterized by 

 the numbers of species of antelopes of various genera 

 which swarm on its open plains, as well as by giraiies, 

 zebras, rhinoceroses, elephants, hippopotami, wart-hogs, 

 bush-pigs, lions, leopards and various other large cats, 

 baboons, man-like apes, and ostriches. On the other 

 hand, with the exception of one living species of bush-pig 

 and a fossil hippopotamus, not a single representative of any 

 one of these groups is met with in the adjacent island ; and, 

 as has been pointed out by Mr. Wallace, it would appear 

 quite probable that both the pig and the hippopotamus 

 may have obtained an entrance by being carried across the 

 channel — possibly at a time when it was somewhat less 

 broad than at present. In place of the animals mentioned 

 above, we find in Madagascar numbers of lemurs, all belong- 

 ing to genera and species distinct from those inhabiting 

 either Africa or India, and so numerous that they form nearly 

 one-half of the whole mammalian population of the island. 

 Civet and ichneumon-like carnivores, likewise pertaining to 

 peculiar genera, are also abundant, and these seem to affiliate 

 the fauna to Africa rather than to Asia, seeing that such 

 animals are more numerously represented in the former 

 than in the latter continent. Among the most remarkable 

 of these civet-like creatures is the so-called fossa 

 (Cruptoproda), which has a uniformly sandy coat, and 

 may be compared in point of size to a short-legged lynx ; 

 this creature differing so markedly from all its allies as to 

 be entitled to represent a distinct sub-family by itself. It 

 has, indeed, been considered that the fossa is closely allied 

 to certain extinct carnivores from the lower Tertiary 

 deposits of Southern Europe, and although some writers 

 are disinclined to accept the relationship, it is not 

 improbable that the theory is well founded. One of the 

 most remarkable features connected with the mammalian 

 fauna of the island is the circumstance that the family of 

 the insectivorous order known as the Centetidce is repre- 

 sented elsewhere only in the West Indies, although the 

 generic forms inhabiting the two areas are distinct. 

 Another apparent indication of American aftinities is 

 afforded by the presence of iguana lizards (Ii/uoniihv), 

 which are now unknown in any other part of the Old World 

 except the Fiji and Friendly Islands. Iguanas are, how- 

 ever, found in a fossil state in the lower Tertiaries of 

 Europe, and it therefore seems probable that their present 

 anomalous geographical distribution may be explained by 

 dispersal from a common northern centre, although it has 

 been thought to indicate a connection between Madagascar 

 and South America. If this be so, a similar explanation will 

 hold good in the case of the Centetiche, although, in spite 

 of statements to the contrary, these have not yet been dis- 

 covered in a fossil state. It will likewise serve with regard 



to the occurrence of an identical genus of freshwater tor- 

 toises in ]\Iadagascar and South America, and also of certain 

 resemblances between Malagasy and Australian reptiles. 



With regard to the former connection between Mada- 

 gascar and the mainland, the occurrence of marine strata of 

 Eocene age in Egypt and other parts of Northern Africa 

 proves that, at the period of their deposition, the portion of 

 the latter continent lying to the south of the Sahara was 

 cut oif from Europe and Asia by an arm of the sea, so as to 

 form an island-continent, in the same way as was South 

 America during some part of the Tertiary epoch. Probably, 

 soon after this, or in the upper Eocene period, this 

 Ethiopian island, as it may be called, of which Madagascar 

 evidently formed a part, was temporarily connected with 

 the northern land, when it received its fauna of civets, 

 lemurs, and insectivores, which a subsequent disconnection 

 allowed to develop without persecution from higher forms 

 of later age. During this time Madagascar became 

 separated, and in the upper Miocene or lower Pliocene age 

 Southern Africa once more became connected with Europe 

 and Asia, which (like North America) were then the home 

 of the various large mammals mentioned above, as well as 

 ostriches. This connection thus allowed a later and more 

 highly organized fauna to sweep over Asia, where it found 

 a free field to develop at the expense of creatures of a lower 

 type. On the other hand, the isolation of Madagascar 

 allowed the more primitive fauna to remain there unmo- 

 lested, and to attain a richness of development which was 

 never reached elsewhere. As to the date when the 

 ancestors of the gigantic flightless Malagasy birds known 

 as .]\pi/iiniis obtained entrance into the island, further 

 evidence seems necessary, as we are not at present aware 

 that any nearly allied forms existed in the European 

 Eocene, unless, indeed, we are to look upon (instornis of 

 the London Clay and corresponding strata of the Continent 

 in that light. The giant tortoises, whose remains are 

 found in the superficial deposits of Madagascar, belong to 

 a group which was widely spread over Europe in Tertiary 

 times, and their ancestors may consequently have entered 

 with the primitive insectivores, civets, and lemurs. From 

 Madagascar, according to the views of Mr. Wallace, the 

 adjacent islands, which, in comparison, are exceedingly 

 poor in mammals, received tuch forms of life as were 

 capable of crossing the intervening sea ; while, in their 

 turn, they formed the stepping-stones by means of which 

 the larger island was populated by such Indian birds and 

 insects as had been able to reach them. 



At the present day, the existing lemurs of Madagascar 

 may be compared in point of size to small or medium- 

 sized monkeys, the largest of them — the short-tailed 

 indri — not measuring much more than a yard in length. 

 The investigations recently carried on by various intrepid 

 explorers in the island have, however, revealed the fact 

 that up to a very late period Madagascar was the home of 

 a lemur vastly exceeding in size any of the existing 

 representatives of the group, and which in this respect 

 may be compared to the great West African baboon known 

 as the mandril. This giant lemur {Mi'iinladaph, as it is 

 called by its describer, I)r. Forsyth Major) is known by the 

 somewhat imperfect skull and lower jaw, which are about 

 three times the dimensions of those of the indri. The interest 

 of this animal is, however, by no means confined to its 

 comparatively gigantic proportions, since while its skull and 

 leeth conform in their general structural features to those 

 of the existing members of the group, they are specially 

 modified m a manner altogether peculiar. The most 

 striking peculiarity connected with the skull is the extreme 

 slenderness of the hinder portion containing the brain in 

 comparison with the great elongation of the face ; the 



