200 Mr. G. Doll man 07t 



Aotus n'lgriceps, sp. n. 



Allied to Aotus holiviensis, Elliot, but having the head- 

 stripes much broader aud continued back further on the 

 crown ; skull with much smaller orbits. 



Size as in A. holiviensis. General colour of back greyish 

 olive, rather darker in the mid-line, where the grey is suffused 

 ^^ith a buff-coloured tint. Flanks and upper sides of limbs 

 dull grey. Backs of hands and feet dark brownish black. 

 Lateral head-stripes black, rather broad and extending back 

 on to the posterior part of the crown. Median stripe diamond- 

 shaped, extending back almost as far as the lateral stripes, 

 but not uniting w ith them. Light marks above eyes white, 

 speckled with black. Under surface of body and limbs 

 yellowish (ochre-colour no. 1, * Repertoire de fyouleurs'). 

 Tail very similar to that ol A. loliviensis, but rather darker 

 to\Aards the tip. 



Skull much narrower across orbital region than that of 

 A. loUviinsis. 



Dimensions of the type (measured in skin) : — 



Head and body 380 mm. ; tail 387 ; hind foot 88. 



Skull: greatest length 63*4; basilar length 41 ; zygomatic 

 breadth 39 ; greatest breadth across orbital region 44 ; 

 condylo-basilar length 47 ; palatilar length 18 ; length of 

 upper tooth-row, from front of first premolar to back of last 

 molar, 15. 



Hub. Chanchamayo, Peru. Altitude 3000 feet. 



Tiipe. Adult male. B.M. no. 5. 11. 2. 2. Collected in 

 Febiuaiy 1904 by C. O. Schunke. 



Ten otherspecimens from Cliancbamayohave been examined, 

 and tiiey all agree with the type in the arrangement of the 

 black head-stripes and the possession of small orbits, characters 

 that justify this Peruvian form being considered distinct 

 from the Bolivian species. 



Aotus Senear, sp. n. 



Similar to Aotus holiviensis, Elliot, as regards the head- 

 stripes, but with a pure black tip to the tail and a very much 

 sn^aller and narrower skull. 



Hair of medium length, measuring about 30 mm. long on 

 the back. General colour of back greyish buff, darker down 

 the middle (brown-pink no. 1, ' Repertoire de Couleurs '), 

 becoming paler and greyer on the flanks and upper side of 

 limbs. Individual hairs of back black at base ; terminal half 

 of hairs composed of four allernate lings of buff and black. 

 Head-stripes black and \ery narrow ; lateral stripes on head 



