2 ARKIV FÖR ZOOLOGI. BAND 14. NIO 20. 



occiput is almost as black as the back. The difference in 

 colour is not connected with the sex, as is proved by the 

 specimens of the former coUection, in which as well light- 

 headed as dark-headed males were found. 



Lagothrix iiifumata Spix. 



1 ^ -yi 1921, »near river Napo», 2000 f. alt.; 1 c? -^3 

 1921, »alongside river Napo», 2500 f, alt. The former of 

 these resembles in colour the one described in my »Second 

 Contrib. to Mammalogy of Ecuador».' The latter is some- 

 what paler, the general colour of the upper parts being 

 rather similar to ^yellowish buff» (Rép. de coul. 310,2) with 

 the dark subterminal rings and the white tips to the hairs 

 only little pronounced. 



Ålouatta palliata quichua Thomas. 



A complete female specimen, 3 skulls of the same sex 

 and a male one from Gualea, 4000 f. alt. 



Ålouatta juara Elliot. 



1 J*, 25/i 1921, »near the river Napo», 2000 f. alt. This 

 species has been established on two specimens in Brit. Mu- 

 seum from »Rio Juara, Upper Amazon» 1910. It was there- 

 fore of great interest to receive this specimen from Napo. 

 Its colour is wben compared with Red Howling Monkeys 

 from f. i. Brazil very striking by the deep maroon of the 

 legs, head and basal portion of the tail in vivid contrast to 

 the golden red of the back. The dimensions of the skull 

 are smaller than those of Elliot 's type, but such charac- 

 teristics are rather variable in these monkeys, so that I do 

 not dåre to assume a smaller race at Rio Napo, if it is not 

 proved by more material. 



Ark. f. Zoologi, Bd. 14, N:o 4, 1921. 



