MAMMALS THA T GNA W. 117 



thick-skinned animals, they like to wallow in mud. They work out 

 hollows in the ground, in which they wallow ; these are known as carpincho- 

 baths. The carpincho does not go to ground, but lives on the banks of the 

 rivers in such cover as it can find. It is capable of remaining under water 

 and of proceeding for some distance under the surface ; but when a herd has 

 been disturbed at a laguna, the members probably lie low by putting just 

 their noses above water under the shelter of a bed of camelotes orother 

 water-plants. I am puzzled to say how many young they have at a birth. 

 On the 8th May I saw two females, each with a young one, about 18 inches 

 long, at her side. I have never seen more than one young one with a female, 

 but this I have often seen ; the young one keeps close to its mother's side, 

 and they plunge into the water together. I am aware that the supposition 

 that the carpincho has only one young one at a birth is contrary to what has 

 been written about this animal ; but I merely give my own observations for 

 what they are worth." 



The two last families of the order, constituting the group Lagomorpha, 

 differ from the rest in having a small second pair of upper incisors behind 

 the large ones of the upper jaw ; the latter being also 



peculiar in that the coating of enamel, instead of being con- Picas. Family 



fined to the front surface, extends round to the back. Lagomyidce. 

 Young animals have three pairs of upper incisors. The 

 small Rodents known as picas, or tailless hares, all of which are included in 

 the single genus Lagomys, are characterised by the equality in the length of 

 the limbs, the absence of a tail, the 

 short ears, complete collar-bones, and 

 rootless molars, divided into transverse 

 laminae by complete folds of enamel. 

 The living species have two pairs of 

 premolar teeth in. each jaw, and the 

 skull has no postorbital processes. Re- 

 presented by about a dozen species, 

 the picas are chiefly inhabitants of the 

 Himalaya and the highlands of Central 

 and Northern Asia, although one out- 

 lying form inhabits South - Eastern Fig. 65. A PICA (Lagomys). 

 Europe, and a second the Rocky Moun- 

 tains. These little creatures dwell in the chinks and crevices of rocks, from 

 which they dart out with remarkable celerity, uttering at the same timo 

 their peculiarly shrill cry. 



From the picas, the hares and rabbits (Lepus) are at once distinguished by 

 their elongated hind-limbs, long ears, short, upwardly-bent tail, arid imper- 

 fect collar-bones ; while the skull differs in possessing large 

 postorbital processes, and there are three pairs of premolar Hares and 

 teeth in the upper jaw and two in the lower. Whereas Rabbits. 

 there are five toes to the fore-limbs, the hind pair has but Family 



four, and the soles of all four are as fully haired as the rest Lcporidce. 

 of the limbs ; the inside of the cheeks being also hairy. 

 There are rather more than a score of species belonging to the genus, which 

 has an almost cosmopolitan distribution, although more numerous in the 

 northern hemisphere than elsewhere, being absent from Madagascar and 

 Australasia, and represented only by a single species in South America. All 

 are very much alike in external appearance. Of the European species, the 



