150 Ipswich Museum. 
arctic latitudes, where the food of the species is wholly absent. If 
we are still to apply the current hypothesis to this problem in Natural 
History, we must suppose that the pair or pairs of the Rhea that 
started from the highest temperate zone in Asia capable of sustaining 
their life, must have also been the same individuals which began to 
propagate their kind when they had reached the corresponding tem- 
perate latitude of America. But no individuals of the Rhea have 
remained in the prairies or in any part of North America—they are 
limited to the middle and southern division of the South American 
continent. And now, finally, consider the abode of the little Apteryx 
at the Antipodes, in the comparatively small insulated patch of dry 
land formed by New Zealand. Let us call to mind its very restricted 
means of migration—the wings reduced to the minutest rudiments, 
the feet webless like the common fowl’s, its power of swimming as 
feeble! How could it ever have traversed six hundred miles of sea, 
that separate it from the nearest land intervening between New Zea- 
land and Asia? How pass from the southern extremity of that con- 
tinent to the nearest island of the Indian Archipelago, and so from 
member to member of that group to Australia—and yet leave no 
trace behind of such migration by the arrest of any descendants of 
the migratory generations in Asia itself, or in any island between Asia 
and New Zealand ? 
If these facts were inexplicable on the hypothesis of the dispersion 
of the species of the air-breathing animals from a singular Asiatic 
centre, we must next endeavour to collect analogous facts, and classify 
them, and so try to explain intelligibly, ¢. e. agreeably with the facts, 
the true law or cause of the actual geographical distribution of ani- 
mals. The time allotted to the lecture obliged the Professor to 
limit his remarks on this subject to the quadrupeds of the class 
Mammalia. 
The dry land of our planet might be divided, in relation to this 
inquiry, into the followmg parts :—1. Asia and Europe, which ob- 
viously formed one natural tract or continent; 2. Africa; 3. North 
America ; 4. South America; 5. Australia; 6. Scattered islands, as 
New Zealand, separated by hundreds of miles of sea from any con- 
tinent. The most characteristic aboriginal quadrupeds of the first 
division were the elephant, rhinoceros, ox, deer, tiger, bear, hyzena, 
beaver, hares and rabbits, certain kinds of ape and monkey. In 
Africa, the quadrupeds were for the most part similar as to genus, 
but different in species. The elephant differed in the structure of 
its teeth and feet from that of Asia. The rhinoceros of Africa had 
two horns, that of Asia one horn. The camel of Asia has two 
humps, that of Africa one hump. The lion represented in Africa 
the tiger of Bengal. The hyzena of Southern Africa was spotted, that 
of Asia was striped. There were also several quadrupeds of which 
no species now exists in Asia, and which are peculiar to Africa; e. g. 
the hippopotamus, the giraffe, the orycteropus, &c. Africa is also 
remarkable for its numerous species of large antelopes, of which but 
few exist in Asia, and none at all in America. In the northern 
division of the American continent, many of the mammalian genera 
