18/2.] DR. J. MURIE ON MACACUS CYCLOPIS. 779 



collection of Rhesus crania in the British Museum, and, taking age 

 and other attributes into consideration, am reduced to the following 

 weak marks of diagnosis : — 



In the <J M. cyclopis the nasals are a trifle broader than in M. 

 erythrceus. The ascending process of the malar bone of the former is 

 rather wider, and its horizontal limb perceptibly deeper than in the 

 latter. In the <$ > but not in the $ , Formosan species there is some- 

 what more fulness of the maxillo-premaxillary region, contrasted with 

 the same in the Indian form. Superiorly the skulls of the above 

 two first-mentioned animals appear to have, rather than absolutely 

 have, greater length to breadth. The inferior aspect of the petrous 

 portion of the temporal bones of the 6* of M. cyclopis is less pro- 

 minent than that of the 3 M. erythrceus, but is equal to the female 

 of the latter. 



Thus there are no very positive points of cranial differentiation dis- 

 cernible. Even the above evince instability when the 2 sexual dif- 

 ferences of Swinhoe's animal are added as a supplement ; to wit, the 

 face is narrower, and the ridges &c. are less prominent. On the 

 contrary, the remarkably abnormal pelvis and shorter limb-bones &c. 

 are weighty, and, indeed, to me conclusive argument in sustaining the 

 claim of the Formosan Monkey to be specifically distinct from the 

 Rhesus. 



I append a series of measurements of the male and female skulls, 

 which, if not exhibiting specialities, may be useful for future com- 

 parisons : — 



Extreme length, praemaxillse to occiput 4*7 4*2 



Greatest width across the malar arches 3*35 2*9 



Length, cranial axis, supraorbitals to occiput 3*55 3*2 



Transverse cranial diam. at the squamosals 2*4 2*9 



Frontal width, groove behind orbits 1*9 1*9 



Vert, height, mid. sag. suture to ant. foram. mag. . . 2*2 2*0 



Depth, mid-frontal to ditto 2*3 2*2 



Extreme height with the mandible 3*42 3'2 



Face, supraorb. ridge to tip of prsemaxillse 2*2 1*92 



Distance, supraorb. ridge to end of nasals 1*18 l'O 



Greatest orbital width 2-8 2'5 



Breadth, maxillae oppos. 2nd premolars 1*5 J '3 



Palatal length 1-9 1-65 



Dist. between posterior nares and foramen magnum . 1*5 1*3 



Width between the postglenoidal tubercles 2*4 2*35 



Mandible in extreme length 3*2 2*85 



Its vertical height at coronoid process 1"75 1'75 



Macacus cyclopis, Swinhoe. 



Characters. External : — Fur thick, wooly, and more slate- 

 coloured than in the Rhesus. Tail about a foot long, hairy, with a 

 black line along the top. Head round ; ears small, feathered ; face 

 flat ; forehead naked ; dark-whiskered cheeks ; strong, ruffle-like 

 beard. In $ , callosities and genitalia periodically enormously de- 

 veloped. Skeletal : — Great curvature of the pelvis, and especially of 



