The Zoological Relations of Madagascar and Africa

Abstract

WITHOUT entering into the details of this very difficult question I wish to be allowed to state some of the general reasons which have led me to a different conclusion from Dr. Hartlaub,2 and also to point out where he has not quoted my opinions with perfect accuracy. Instead of saying that “the fauna of Madagascar is manifestly of African origin,” my actual statement is as follows:—“We have the extraordinary fauna of Madagascar to account for, with its evident main derivation from Africa, yet wanting all the larger and higher African forms; its resemblances to Malaya and to South America; and its wonderful assemblage of altogether peculiar types” (“Geog. Dist. of Animals,” vol. i. p. 286). My reasons for believing in the “main derivation” of the fauna from Africa can only be understood by considering the theory, now generally admitted, of the origin of the fauna of Africa itself. All the higher mammalia are believed to have entered it from the northern continent during the middle or latter part of the tertiary period, and the occurrence of Psittacus and of forms supposed to be allied to plantain-eaters and to Leptosomus in the miocene of France, render it probable that many of the peculiar groups of African birds had their origin in the old Palaearctic region. Now Madagascar presents many cases of special affinity with South Africa, especially in insects, land-shells, and plants; and if we suppose it to have formed part of a South African land before the irruption of the higher mammals and birds from the north, we shall I think account for many of its peculiarities. Such facts as its possessing Potamochaerus and the recently extinct Hippopotamus, while it has thirteen or fourteen peculiarly African genera of birds against four or five that are peculiarly Oriental; of its having many African genera of lizards and tortoises; of its butterflies being decidedly African; of its numeious African genera of Carabidae, Lucanidae, and Lamiidae; while the specially Oriental affinities of its mammals, reptiles, and insects are hardly if at all more pronounced than the South American affinities of the same groups,—all seem to me to warrant the general conclusion that the “main derivation” of the Madagascar fauna is from Africa.