FAUNA AMERICANA. 279 



CHARACTERS. 



{rincisor 0. 

 superior 2. < Canine 0. 

 rSsorO.' 

 inferior 2. < Canine 0. 

 C-Molar 2. 



No implanted teeth, only a molar plate on each 

 side of the jaws, attached by numerous vessels 

 and nerves ; triturating surface unequal, and groov- 

 ed by tortuous canals. 



Body ventricose in the middle, and tapering 

 gradually as far as the caudal fin. 



Head obtuse, without a distinct neck. 



No external ears. 



Upper and lower lips double. 



Eyes furnished with a cartilaginous membrane 

 in form of a crest, which occasionally covers them. 

 Nostrils placed towards the extremity of the snout. 



Anterior extremities in form of palmated fins, 

 like those of the sea turtle. 



Caudal fin very broad, not very long, cruciform^ 



Skin destitute of hair, but clothed with a very 

 solid, thick epidermis, and composed of compact 

 tubes or fibres perpendicular to the skin. 



Stomach simple. 



* Species. 



I. Stellerus borealis, Cuv. Desm. Manatus, 

 Steller. Trichechus manatiis, Var. borealis, Grael. 

 Trichechus borealis, Shaw, Gen. Zool. Whale- 

 tailed Manati, Penn. Grand Lamantin du Kam- 

 schatka, Sonnini, Nouv. Diet. d'Hist. Nat. 1. edit. 



