Hares (and rabbits) have a cosmopolitan distribution with the exception of Madagascar and Australasia; and are now divided into numerous genera and subgenera, mentioned in the article FIG.
All the European hamsters show more or less black on the under-parts, but the small species from Central Asia, which constitute distinct subgenera, are uniformly grey.
SPINY SQUIRREL, a book-name for a group of African ground squirrels, characterized by the spiny nature of the fur of the more typical forms. They form the genus Xerus, which is split up into a number of subgenera; Xerus rutilus of Abyssinia and East Africa belonging to the typical group, while the striped North African X.
In 1855 Gray brought out, as one of the Museum publications, A Catalogue of the Genera and Subgenera of Birds, a handy little volume, naturally founded on the larger works.
More than this, he seems to be the earliest ornithologist, perhaps the earliest zoologist, to conceive the idea of each genus possessing what is now called a " type " - though such_a term does not occur in his work; and, in like manner, without declaring it in so many words, he indicated unmistakably the existence of subgenera - all this being effected by the skilful use of names.