3S8 LASIOPYGA 



Even comparing the skull of the male from the Benito River with the 

 type of L. g. pallida, the much higher elevation of the frontal bone in 

 the skull of the latter is clearly perceptible, and the more prominent 

 anterior portion of the nasals is also easily noticed. These differences 

 in colors and cranial characters seem to warrant the separation of the 

 Gaboon Monkeys, as a race at least, from L. grayi. 



Lasiopyga petronell^ (Buttikofer) . 



Cercopithecus petronellcc Buttikofer, Notes from Leyden Museum, 

 XXXIV, 1911, p. 1. 



WHITE-CROWNED GUENON. 



Type locality. Upper Congo, exact locality unknown. Type in 

 Leyden Museum. 



Color. "A narrow, but rather high median crest, beginning near 

 the front and ending on the center of the crown, entire hinder crown, 

 occiput and hind neck down to the shoulders olive-green, speckled with 

 black, each hair being black with commonly two broad yellowish rings, 

 of which the outer one is subterminal, leaving a long black tip to each 

 hair. Whole back from the shoulders to the root of the tail, and even 

 extending upon the latter, rich chestnut-brown, with black specklings, 

 pioduced by the black tips to each hair. No black on the arms, their 

 outer surface being olive-green like crown and hind neck ; outer surface 

 of legs olive yellow, faintly speckled with black; no white patches on 

 crupper, hands and feet grayish, scarcely tinged with olive. Front 

 and sides of anterior crown white, faintly speckled with black, the 

 white crown patches separated by the narrow olive-green crest, and 

 bordered on the outside by a broad, pure black band, running from the 

 orbits to and even below the ears. Long, bushy whiskers below this 

 black stripe, and a long tuft of hairs in the ears, proceeding far behind 

 the top of the hinder edge of the ear, yellowish white. Chin, throat, 

 breast and inner surface of arms white, with a yellowish tinge, belly 

 and inner surface of legs uniform ochraceous yellow. Tail olive green 

 on its basal half, passing into black on the terminal half and becoming 

 pure black at the tip. Skin of face blue, upper and lower lip flesh- 

 color, covered with very short white hairs, intermixed with sparsely- 

 set long, bristly hairs which, like the long hairs of the eyebrows, are 

 black. Skin of the whole body underneath the fur, light blue. Iris 

 light chestnut-brown." 



Measurements. "Total length, 1,020; tail, 640; fore-arm from 

 elbow to tip of fingers, 170 ; leg from knee to heel, 140 ; foot from heel 

 to tip of toes, 120." 



