j6 Bulletin American Museum of Natural History. [Vol. XX, 



complete, blackish eye-ring; ears externally blackish and quite large; 

 ventral surface pale yellow, suffused with pale brownish rufous over 

 the fore neck, darkening to a rusty pale chestnut median band on the 

 chest, and on the abdomen to dark chestnut; limbs externally like 

 the sides of the body, darkening slightly on the toes; tail above like 

 the back, that is reddish brown with a darker median band, which ex- 

 pands apically to occupy the whole upper surface; lower surface of 

 tail dull brownish yellow. 



The four specimens agree in their generally very dark (blackish) 

 coloration above, but vary a little in the amount of reddish brown 

 suffusing the surface of the dorsal pelage. 



Measurements. Type, $ ad., total length, 874; head and body, 

 430; tail vertebrae, 444; hind foot (without claws), 79; ear, 36. An- 

 other specimen, ? ad.: Total length, 843 ; head and body, 413; tail 

 vertebrae, 430; hind foot, 73; ear, 35. The skulls of these specimens 

 measure, respectively: Occipito-nasal length, $ 89, ? 86; basal 

 length, $ 83.5, ? 78; zygomatic breadth, $ 60, ? 57-5; interorbital 

 breadth, $ 17, ? 18; width of braincase, $ 40, $ 41; length of 

 palate, $ 36, ? 36; upper premolar-molar series, $ 20, ? 20; lower 

 premolar-molar series, $ 23, ? 22; length of lower jaw; $ 61, ? 58; 

 height at condyle, $ 29.5, ? 27.5; height at coronoid, $ 41, ? 41.5. 

 These specimens are both middle-aged adults. 



This subspecies needs no comparison with P. /. megalotus 

 (as represented by Santa Marta, Colombia, specimens), being 

 so widely different in color; and it is equally distinct in 

 coloration from P. /. chiriquensis , and radically distinct from 

 it in cranial characters. It belongs to the group having the 

 palatal floor posteriorly depressed, and with the teeth rela- 

 tively small, and should be perhaps compared with P. /. 

 modestus, from southwestern Ecuador, which it apparently 

 approaches in coloration, but exceeds in size. It also has a 

 general resemblance in coloration to P. /. meridensis, but the 

 yellow of the lower parts is paler and much less suffused with 

 orange, and it appears to be much larger. 



Potos flavus chapadensis, subsp. nov. 



Type, No. -W/ 3 ? ad., Chapada, Matto Grosso, Brazil, August, 

 1885; Herbert H. Smith. 



Above dull yellowish brown, the tips of the hairs blackish; an in- 

 distinct and somewhat interrupted dark dorsal stripe from behind 

 the shoulders to the rump; top of head rather darker than back, 

 through the greater abundance of blackish- tipped |hairs ; ears large, 



