UODENTIA. 139 



Kerodon, Fred. Cuv. 



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

 formed of two triangular prisms. 



The only species known is also from Brazil, somewhat surpasses 

 the Guinea-Pig in size, and is of an olive-grey. 



Chloromys, Fr. Cuv. — Dasyprocta, Illig, 



The Agoutis have four toes before and three behind; four grinders 

 throughout, almost equal, with flat crowns irregularly furrowed, rounded 

 borders, notched on the internal edge in the upper jaw, and on the exter- 

 nal one in the lower. In disposition, and in the nature of their flesh, 

 they resemble Hares and Rabbits, which they may be said to replace in 

 the Antilles and tropical portions of America. 



C. acuti ; Cavia acuti, L. ; BuiF. VIII. 1. 1, (The Common 

 Agouti). The tail reduced to a simple tubercle ; fur brown. The 

 male fawn coloured on the croup ; as large as a Hare. 



C. acuchi ; Cavia acuchi, Gm. ; Buff. Supp. III. xxxvi. (The 

 Acouchi). Six or seven vertebras in the tail; brown above, fawn 

 coloured beneath; size of a Hare. 



C. patagonicus ; Cavia patagonica, Penn. and Schreb. ; the 

 Pampas Hare of the Creoles of Buenos Ayres. This animal 

 appears to be a species of Agouti, with longer ears, and a very 

 short naked tail; but its molars are not known. 



CCELOGENYS, Fr. CuV.* 



The Pacas, in addition to teeth very like those of the Agoutis, have a 

 very small additional toe on the internal edge of the fore foot, and one on 

 each side, equally small, on their hinder one, making five toes every 

 where. Besides this, there is a cavity formed in their cheek which dips 

 under the border formed by a very large and projecting zygomatic arch,-|- 

 which gives a very extraordinary aspect to the bony head. Their flesh 

 is said to be very good. 



There is one species or variety fawn coloured, and another brown, 



both of which are spotted with white, the Cavia paca, L. ; Buff. X, 



xliii. ; Supp= III. xxxv. 

 Finally, there remains an animal perhaps nearly allied to the Cavias, 

 and possibly more so to the Lagomys, or the Rats, which we are unable 

 dispose of, on account of our ignorance of its teeth : this is the Chin- 

 chilla, whose skins arrive in such abundance for furriers, but of which 

 we have never yet been able to procure the entire body. It is the size of 

 a Guinea-Pig or small Rabbit ; is covered with long and close hair of the 



* Ancema, without strength; Chloromys, yellow rat; Dasijprocia, hairy buttock; 

 Coelogenys, hollow cheek ; Hydrochcerus, water-pig. 



t Dr. Harlan (Faun. Americ. p. 126) has made a new genus from a head pre- 

 served in the Philadelphia Museum, which he names Osleopera; but, from the de- 

 scription, it appears to us to be nothing more than that of the Paca. Desmarets has 

 already made the same observation. 



