500 ZOOLOGY. 
those parts inhabited by the largest and most carnivorous of Carnivora. In 
North America, where Carnivora are comparatively scarce, ruminants are 
much less numerous. ; 
The genus Camelus is peculiar to the old contineut, and the genus 
Auchenia to the new; they are two equivalent groups. The aberrant 
giraffe is exclusively hacia The antelopes proper are also absent from 
the New World. A single species occurs in North America, the ied 
Mountain antelope (Anti locdhont americana). 
The rodents constitute the most numerous order of the class of steicnaii 
and are at the same time among the smallest. 
The family of Leporidee has representatives both in the Old and New 
Worlds, but they are chiefly confined to the northern hemisphere; some, 
like the Lepus glacialis, extend into the polar regions. About 35° south 
latitude is the most southern range of the family in either hemisphere. 
The great continent of South America has yielded but a single species, 
and that does not occur south of the Rio de la Plata; whilst, on the other 
hand, it is in North America that the species are proportionally more 
numerous. In the Old World, the group in like manner almost disappears 
in the tropical portions; it reappears, however, south of the tropics, there 
being several species found at the Cape of Good Hope. But one species 
has been discovered in the Indian islands, and in Australia there are no 
hares; indeed, all Rodentia found in that continent belong to the ey 
Muride. 
The hystricine rodents are essentially South American, and under that 
head we include Hystricide, Dasyproctidze, Echimyide, Octodontide, Chin- 
chillide, and Cavide. Hystricide has a wide geographical range, having 
representatives in the four quarters of the globe, with the exception of two 
species, Aulacodus swinderianus and Pteromys typicus; the whole of the 
species forming the five remaining sub-families are exclusively found in the 
New World, being chiefly confined to South America. 'T'wo or three spe- 
cies in the West India islands, and about the same number in Central 
America, form the exceptions. The members of the Hystricide, Dasy- 
proctidee, and Hchimyide increase in number towards the tropical portion 
of South America; whilst in the southern part of that continent, the less 
highly organized species only are found, these being members of the Octo- 
- dontidze, Chinchillide, and Cavide. On the western side of the southern 
Andes the Octodontidz alone have representatives. 
The Saccomyina are exclusively American, from the extreme north to 
Colombia and Guiana, the greatest development of the group being in 
Central America. 
The Bathyergina are African, three species constituting the group, 
forming two genera. ‘The Arvicolina are excluded from Africa and Aus- 
tralia, but are found in North America, Northern Asia, and Europe. The 
Spalacina are not found in the New World; three species are Kuropean and 
three African; the remainder are Asiatic. The Murina are common to 
both hemispheres. The domestic mice and rats have spread all over the 
world; each country also possesses its own kinds. Furthermore, we 
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