1865.] Sclatee on the Mammals of South America. 617 



Habrocoma, Octodon, Schizodon, Spalacomys, and Ctenomys, which inhabit 

 the middle and southern parts of that continent, occurring on both 

 sides of the Andean range. They are all of small size, and are partly 

 of burrowing, partly of more or less climbing, habits, agreeing with 

 the Cavies and Chinchillas in having rootless molars, but readily 

 distinguishable from these two families by the possession of five well- 

 developed toes on the hind feet. The Spalacomys poeppigii presents 

 a curious deviation in mode of life from the rest of the group in 

 living nearly entirely under ground, and only occasionally emerging 

 at night-fall. In the next sub-family (the Echimyina) we meet with 

 two African types, Peiromys and Aulacodus. The remaining genera, 

 Capromys, Myopotamus, Cercomys, Dactylomys, Loncheres, and Echimys, 

 are all exclusively Neotropical types. Capromys and Plagiodus are 

 characteristic forms of the Antilles. The other genera inhabit the 

 northern and central portions of the continent, not, however, as far 

 as I know, occurring northwards of the Isthmus of Panama. The 

 best known animal of this section is, perhaps, the water-loving Coypu 

 {Myopotamus coypus), which has much superficial resemblance to the 

 Beaver (Castor), and has been erroneously associated with that animal. 

 The Agoutis (Dasyproctina) form the fifth subdivision of the great 

 Hystricine family according to Mr. Waterhouse's system. They 

 embrace two genera, Coslogenys and Dasyprocta, both exclusively Neo- 

 tropical. The first-named genus contains but one well-established 

 species, the Paca, Codogenijs paca. Nothing can give a better idea 

 of the poverty of large animals useful for food in the Amazonian 

 forests, than the fact that this little animal and the Coypu are the 

 species most sought after for food by the hungry hunter, who, in a 

 corresponding latitude in Africa would be feeding on the flesh of elands 

 and giraffes. The Agoutis (Dasyprocta) are nine or ten in number, 

 extending from Paraguay and Bolivia into Mexico.* This is also 

 one of the few genera of Mammals (exclusive of Bats) which occur 

 in the West Indian Islands. Lastly, we come to the sixth sub-family, 

 Hystricina, of which the most typical forms, Hystrix and Atherura, 

 are peculiar to the Old World. The American Porcupines form, in 

 fact, quite a separate section of the group to which Professor Brandt 

 has given the name " Philodendreae," from their tree-loving habits. 

 They are divisible into three genera, Erethizon, Cercolahes, and 

 Chcetomys. The first of these is a Nearcticf form, the remaining two 

 are Neotropical. Chwtomys contains but a single Brazilian species ; 

 Cercolahes comprehends a series of a dozen species or so, which are 

 diffused all over the forests of America from Mexico to Paraguay. 



The last family of Eodents, the Hares (Leporidse), contain only 

 two generic forms, Lepus and Lagomys. The latter is an Arctopolitan 

 type, being confined to the Palsearctic and Nearctic regions. Lepus is 

 thinly diffused over the greater part of the world, except the Australian 



* M. de Saussure has lately described a Mexican species, D. Mexicana. * Kev. 

 Zool.,' 1860, p. 53. 



f Dr. Gray has recently described a species of Erethizon from New Granada 

 (E. rufescens, 'P. Z. S.,' 1865, p. 321), but I doubt its truly belonging to this 

 genus ; and Dr. Gray has provided asub-genus for its reception (Echinoprocta). 



