BRADYPUS. 



be separated. Teeth rather small, anterior tooth in the upper jaw 

 smaller than the rest, and none projecting much beyond the others. 

 Superior outline of skull greatly arched; nasals short, broad, pointed 

 posteriorly; interpterygoid fossa very broad and deep; palate nar- 

 rowed posteriorly; arch rounded. Cervical vertebrae, nine; some- 

 times the eighth, and always the ninth, bear short ribs. Windpipe 

 folded on itself before reaching the lungs. Mammas two, pectoral. 



FIG. 5. BRADYPUS INFUSCATUS. 



No. 2824 Am. Mus. Nat. Hist. Coll. % nat. size. 



KEY TO THE SPECIES. 



A. Dorsal patch yellow with black central streak. PAGE 



a. Forehead, cheeks, and chin reddish brown. B. castanciccps 22 



b. Forehead, cheeks, and chin dark brown B. inftiscatiis 23 



17. castaneiceps (Arctopithccns}, Gray, Proc. Zool. Soc., 1871, p. 444. 

 CHESTNUT-HEADED SLOTH. Camalcon in Nicaragua. 



Type locality. Chontales, Nicaragua. 



Gcogr. Distr. Nicaragua, Central America. 



