218 Original Articles. | April, 
mark out the wide difference between these two creations as they stand 
at present. The same is nearly the case as regards the next order—that 
of Pachyderms. The Hippopotamus, so abundant on the opposite coast of 
Mozambique, is not found in Madagascar. Had Madagascar ever formed 
part of Africa this would hardly have been the case. The genus Equus, 
well represented in Southern Africa by the Zebras and Quaggas, the 
Hyrax and the Rhinoceros, is likewise wanting; and of the Artio- 
dactyles only a single species—namely, the South African Riverhog 
(Potamocherus Africanus)—is stated to inhabit Madagascar. But 
although M. Sganzin has positively identified this species as a Mada- 
gascarian animal, I cannot but think it rather doubtful ; in the first 
place, because this is the only exception to the general rule of 
specific (and almost generic) difference between the Mammals of 
Madagascar and Africa; and secondly, because Dr. Peters tells us he 
could obtain no indications of the existence of this Pig upon the oppo- 
site coast of Mozambique. However, until the contrary is proved, it is 
only fair to assume M. Sganzin’s statement to be correct, and to include 
this Riverhog in the list of Madagascarian Mammals. 
Having thus given a cursory view of some of the more salient 
features of the Mammal-creation of Madagascar let us see what deduc- 
tions we can gather from them as to its origin—taking, of course, for 
granted, the derivative hypothesis of the origin of species—at present, 
the only theory by which the otherwise inexplicable facts of geographical 
distribution can be explained. Of course it would be more satis- 
factory in a case like the present to have before us a summary of 
the knowledge we possess concerning every part of the Fauna and Flora 
of Madagascar, but as space does not permit this, let us see what we 
can make out from the Mammals alone. 
The following deductions may, perhaps, be arrived at from what we 
have before us :— 
1. Madagascar has never been connected with Africa, as it at present 
exists. ‘This would seem probable from the absence of certain all-per- 
vading Aithiopian types in Madagascar, such as Antilope, Hippopotamus, 
Felis, &c. But, on the other hand, the presence of Lemurs in Africa 
renders it certain that Africa, as it at present exists, contains land that 
once formed part of Madagascar. 
2. Madagascar and the Mascarene Islands (which are universally 
acknowledged to belong to the same category) must have remained 
for a long epoch separated from every other part of the globe, in order 
to have acquired the many peculiarities now exhibited in their Mammal- 
fauna—e.g. Lemur, Chiromys, Eupleres, Centetes, &e.—-to be elaborated 
by the gradual modification of pre-existing forms. 
3. Some land-connection must have existed in former ages be- 
tween Madagascar and India, whereon the original stock, whence the 
present Lemuride of Africa, Madagascar, and India are descended, 
flourished. 
4, It must be likewise allowed that some sort of connection must 
also have existed between Madagascar and land which now forms part 
of the New World—in order to permit the derivation of the Cente- 
