RODENTIA. 91 



skeleton reticulated. The species are so numerous and similar, that it is 

 difficult to characterise them. 



L. Americanus, Gm. (The American Rabbit.) Nearly similar in size and 

 colour to the European species; feet reddish; no black on either ears or tail. 

 Nestles in the hollows of trees, up which it sometimes ascends as far as the 

 branches. Flesh soft and insipid. 



LAGOMYS, Cuvler*. 



Rat-Hares have moderate ears ; legs nearly alike ; the hole below the eye 

 simple; clavicles nearly perfect, and no tail; they often utter a sharp cry. 

 They have hitherto been found in Siberia only, and it is to Pallas that we are 

 indebted for their discovery. This author describes several species, varying 

 in size and colour, and also in their habits and locality. 



The fossil bones of an unknown species of Lagomys have been discovered 

 in the osseous breccia of Corsica. 



After the two genera of Porcupines and Hares, come those Rodentia united 

 by Linnaeus and Pallas under the name of CAVIA ; but to which it is impos- 

 sible to affix any other common and positive character than that of their 

 imperfect clavicles, although the species of which they are composed are very 

 analogous to each other, both in body and habits. They are all from the 

 western continent. 



HYDROCHCERUS, Erxleben. (2)f 



Four toes before and three behind, all armed with large nails, and united 

 by membranes ; four grinders throughout, of which the posterior are the 

 longest, and composed of numerous simple and parallel lamime ; the anterior 

 laminae forked towards the external edge in the upper, and towards the inter- 

 nal one in the lower teeth. Only one species is known, the Capybara, which 

 inhabits the rivers of Guiana and the Amazon, where they live in troops. 



CAVIA, Illiger. AN<EMA, Fr. Cuvier. 



The Cobuyes, or Guinea- Pigs, are miniature representations of the Cabiais ; 

 but their toes are separated, and each of their molars has only one simple 

 lamina, and one that is forked on the outside in the upper ones, and on the 

 inside in the lower. The best known species is the Mus porcellus, Lin. ; is 

 now very common in England and the rest of Europe ; where it has been 

 domesticated ; it varies in colour. It is found wild in the woods of Brazil 

 and Paraguay. 



KERODON, F. Cuvier. 



The Mocos have rather simpler grinders than the Cobayes, each being 

 formed of two triangular prisms. The only species known is from Brazil ; 

 it is somewhat larger than the Guinea-Pig, and is of an olive grey. 



* Lagomys, i. e. Rat-Hares. f Hydroclmrus, Water-Pig. 



