728 ALOUATTA. AOTINA. AOTUS. 
IsLAND OF Co1BA HOWLER. 
Type locality. Coiba Island, off west coast of Panama. 
Genl. Char. Similar to A. palliata, but smaller; zygomata pro- 
portionally more expanded. A small insular race. 
Color. Like A. palliata. 
Measurements. Head and body, 560; tail, 580; foot, 130. Skull: 
greatest length, 104.5; basal length, 86.5; zygomatic breadth, 79.5; 
nasals, median length, 15.3; anterior width, 13.5; least width, 7.5; 
interorbital breadth, 11; palatal length, 53; length of upper tooth 
row (molars and premolars), 33; condyle to angle of mandible, 62; 
antero-posterior diameter of ascending ramus, 30. 
Subfam. Il. Aotinee. Squirrel Monkeys. 
Size small; tail non-prehensile; muzzle not prominent; habits 
nocturnal. 
175. *Aotus. 
= C= _ P3 : M.= 20 
Aotus Humboldt, Recueil d’obs. Zodl. et Anat. Comp., I, 1811, p: 
358. Type Sima trivirgata Humboldt. 
Nycttpithecus Spix, Sim. et Vesp. Bras., 1823, p. 25. 
Head round; orbits large; nasal septum narrow; nostrils approxi- 
mate. 
Fic. 165. AOTUS AZARA. 
No. 37793. Coll.U.S Nat. Mus. Nat. size 
*To illustrate this genus, no skull of a Central American species being 
available, that of a South American species is given. 
