the Genus Cercoccbus. 283 



type, makin;^ a total of two adult males and one adult and 

 two young feuialcs. 



7. Helmeted Mangabey. 



Cercocehus galeritus^ Pet. 



Cercocebus galeritusy Peters, Mon. Akad. Berlin, 1879, p. 830, pis. i.* & 

 iii. ; Matschie, Saugeth. Deutsch. Ost-Afr. p. 145 (1895) ; Pousar- 

 gues, Ann. Sci. Nat. (8) iii. pp. 220-235 (1897). 



Loc. Bilt. E. Africa : Tana River. 



This species is known to rae only from the figure and 

 description published by Peters and from the remarks upon 

 it Matschie and Pousargues have published. 



The general colour both above and below seems to resemble 

 that of C. agilis ; but the arrangement of the hair on the 

 crown of the head is quite different from that of C. afjilis and 

 C. Hagenhccki, Judging from the figin-e, whichj according 

 to Matschie, quoted by Pousargues, is correct, the parting is 

 not, as in those species, a small circular area from which the 

 hair radiates, but almost Y-shaped ; the hairs on the forehead 

 turn forwards over the brows and are separated by a transverse 

 parting running from temple to temi)le from the hairs of the 

 top of the head, which are long and directed outwards from 

 a median longitudinal parting, so that their ends overhang, 

 like a roof, the tops of the ears. The description Pousargues 

 gives of this arrangement does not express at all clearly, in 

 my opinion, what the illustration in Peters's paper shows. 

 Trouessart's interpretation is much more in keeping with the 

 figure. But the two species, C. agilis and galeritus, are, I 

 siiould say, much less nearly related than these French 

 authors believed. 



8. The Black Mangabey. 



Cercocebus albigena, Gray. 

 Preshytes albigena, Gray, P. Z. S. 1850, p. 77. 



Loc. Basin of the Congo and E. Africa (Uganda, Tan- 

 ganyika). 



Mr. Lydekker (Xov. Zool. vii. pp. 594, 596, 1900) admits 

 the following subspecies of this form : — 



albigena, Gray, P. Z. S. 1850, p. 77, pi. xvi. 



Loc. French Congo. 

 aterrimusy Oudemans, Zool. Gart. xxxi. p. 267 (1890). 



Loc, Stanley Falls ; north or right bank of Congo. 



