1907. 



MONKEYS OF THE GENUS CERCOriTHEOUS. 



685 



descends to the knee. Apait from this pale stripe the outei' side 

 of the thigli and lower leg is gi'eyish or olive, dai-ker above and 

 over the knee, where the pigmented ai-ea is strongly conti-asted 

 with the white of the innei- side of the thigh ; foot and ankle 

 black. Ventral surface from the chest to the pubic area soot}- 

 olive-grey. 



Distr. Region of Lake Rudolf to the Cameroons and Congo. 



Text-fio-. 180. 



Head of Cercopithecus neglectiis Schlcgel. 

 (From P. L. Sclater, P.Z. S. 1893, p. 255.) 



C. neglectus has hitherto been associated with C. (rZiffl>i« on account 

 of the presence of a white beard and of a white stripe on the 

 external aspect of the thigh arising from a point near the ischial 

 callosity. The importance of these characters as evidence of 

 affinity is, however, lessened by the fact that C. mona has a white 

 patch close to the callosity ; that in C neglectus the white stripe 

 in question starts at a point on a level with the lower mai-gin of 

 the callosity, whereas in G. cliana it arises at its upper margin ; 

 that in C. neglectus the beard is not an isolated tuft depending 

 fi'om the point of the chin, as in C. diana and C. roloicay, but is 

 formed by the elongation of the hairs covering the inferior edge 

 of the lower jaw and of the thi"oat ; and that in G. diana the 

 beard is scarcely developed. These differences, taken in con- 

 junction with the dissimilarities in colour, in the direction of the 

 growth of the hairs on the cheek, destroy confidence in the 

 conclusion that they ai"e to be regarded as criteria of kinship 

 close enough to wan-ant the association of the two species in one 

 section of the genus Gercopithecus. 



It appears to me that the characters of the one known species 

 point to its being an aberi-ant type of the Leucampyx-group. 

 From these it differs principally in the red colour of the brow -band ; 



