276 FAUNA AMERICANA. 



The incisors very small, existing only in the fetus. 

 Adults have only thirty-two teeth, as four molars 

 fall in early life. 



Crowns of the molars present two transverse 

 tubercles, with three points at their summits in 

 the young tooth ; the superior teeth square ; the 

 inferior oblong. 



Head not distinct from the body; eyes very 

 small, placed superiorly, between the end of the 

 nose and meatus auditorius externus, which is 

 scarcely apparent. 



Tongue oval ; posterior parts of the body very 

 thick, depressed and rounded at the end, without 

 a caudal fin, properly so called. 



Vestiges of nails on the borders of the pectoral 

 fins. 



Whiskers composed of a fasciculus of enormous 

 hairs, directed downwards, and forming on each 

 side a sort of corneous tusk. 



Skin naked, very thick and rugous. Penis of 

 the male terminated in a gland, enlarged in form 

 of a mushroom, as in the horse. 



Sixteen pairs of ribs, thick, and solid, the two 

 first only articulating with the sternum. 



Stomach divided into many pouches. Coecum 

 bifurcated. Colon capacious. 



Habit. These animals live in societies, and 

 feed on vegetable substances ; the male displa^^s 

 much attachment to the female, and she much 

 tenderness towards her offspring, which she car- 



