696 AIR. 11. I. rococK — a revision of [June 18, 



Owing to the presence of the nose-spot, the species of this 

 section have been hitherto associated with G. petaurista and its 

 allies. It is possible that the two groups are connected thi'ough 

 such a form as G. signatus, wliich difiers from typical members 

 of the Petaurista-group in the coloration of the cheeks ; but 

 C. nictitans appeal's to me to be much moi'e nearly I'elated to the 

 Leuca.mpyx-group, especially to G. I. boidourlinii, from which it 

 difiei's essentially only in the gi-eater definition of the hairs forming 

 the patch upon the nose and their distinctness from those of the 

 upper lip. 



As beai'ing on the views here expi'essed as to the affinity 

 between C. nictitans and G. leucmnpyx, it is significant that Cuvier 

 called attention to the similarity between his Diane feioaelle, the 

 type of G. leucampyx, and the Hocheur (G. nictitans). 



Distr. Liberia through Nigeria to the Congo and Gaboon. 



The two species referred to this group may be briefly dis- 

 tinguished as follows : — 



a. Breast, belly, and base of fore legs on the inner side blackish ; no 



red on ischio-pubic area nictitans. 



<('. Breast and inner side of arms at base whitish ; some red hairs on 



ischio-pubic region and on base of tail, at least in adult martini. 



The differences between these two species are not very marked. 

 I have not, however, seen any intermediates to justify me in 

 regarding them merely as subspecific foims. Of the two, 

 G. nictitans is much more commonly imported, and may usually 

 be seen in menageries. 



Cehcopithecus nictitans Linn. (Text-fig. 183.) 



Subsp. NICTITANS (Linu.). 



iSi'inia nictitans Linn. Syst. Nat. i. p. 40, 1766. 

 Ge7'copithecus nictitans Erxl. Syst. Regn. Anim. p. 35, 1777, 

 and of subsequent authors. 



Entire dorsal area from forehead to root of tail thickly speckled 

 with yellowish grey ; hairs blacker in front of and behind ears 

 and sometimes slightly so on nape. Arms and shoulders black ; 

 legs blackish but speckled. Tail mostly black, speckled at base, 

 without red hairs beneath. Hairs on throat and chm greyish, 

 a black band across collar-bones ; chest and belly dark grey to 

 blackish, but more or less speckled. No red on ischio-pubic area. 

 Hairs on body with narrow grey annuli. 



Log. From the Cameroons to Oette Cama. 



Pousai-gues records this species from various localities in the 

 French Congo — namely, San Benito, Alima River, Magumba, 

 Banqui, and Cette Cama. 



Since the exact locality of G. nictitans is unknown, I propose to 

 regard as typical of this species a foim represented in. the British 

 Museum by examples from the Benito River, in the Congo, 

 collected by Mr. G. L. Bates. They were taken at sea-level from 



