776 DR. J. MURIE ON MACACUS CYCLOPIS. [June 18, 



the Round-faced Monkey, however, is the breadth and shape of the 

 lateral wing-like transverse processes. In shape these want that 

 squareness which obtains in the Rhesus ; and the anterior process of 

 the first sends forwards a long spicule. 



Mr. Mivart* assigns fifteen caudal vertebrae to Macacus rhesus — I 

 suppose limiting his remark to the <$ specimen, No. 4991, in the 

 College of Surgeons' Museum (also vide Catalogue, vol. iii.). In 

 one skeleton of the same species in the British Museum, there 

 are eighteen separate elements, their entire length being only nine 

 inches. In the female M. cyclopis, with but sixteen vertebrae, their 

 combined measurement is 1 1 \ inches. The proportion borne by the 

 tail to the length of the spine (vide Table, p. 777) is as 99' 1 to 100 

 in the $, 98-4 to 100 in the <J Formosan, and C7"l to 100 in the 

 true Rhesus. It follows that the tail in the former is both abso- 

 lutely and relatively longer, and each vertebra stronger, than in that 

 compared. 



There is another peculiarity possessed by the Formosan Monkey, 

 which allies it with the Baboons. At the distal end of the first 

 caudal the direction of the tail's long axis alters, being tilted up at 

 an angle of about 140°; thence it extends curvilinearly. The 

 said tilt is not due to imperfect mounting ; for the skeleton is a 

 natural or ligamentous one. Moreover the manner of articulation 

 of the bones is conclusive, and unlike what obtains in M. erythrceus. 



Each caudal vertebra is longer than that in advance, until the 

 twelfth is reached, when they successively decrease in size. 



A neural spine is well developed in the first and second. In the 

 third, fourth, and fifth a true elevated spine is absent. The neural 

 laminae, instead, are laterally perforated posteriorly, and reach back- 

 wards as a low arch joining the zygapophyses of the vertebrae 

 behind. From the sixth backwards a centrum only is present. 

 Both in Cercopithecus and Hamydryas the spaces just mentioned 

 are very patent in the corresponding caudals. 



Fair-sized transverse processes obtain from the first to the fourth 

 vertebrae. Chevron bones and tubercles for their attachment (i. e. 

 haemapophyses and hypapophyses) are met with in the anterior 

 caudals. 



The ribs, as in the Macaques generally, are twelve on either side ; 

 and of these, eight are true and four false. 



In the female skeleton eight pieces are extant in the sternum ; but 

 in the male there appear to be only seven. Mivart (I. c.) avers that the 

 number of distinct bones posterior to the manubrium and anterior 

 to the xiphoid cartilage generically varies, but assigns five or six to 

 Macacus and Cynocephalus. The manubrium is large, and not so 

 thick as the body-segments, although in the male the clavicular 

 portions manifest more than the average solidity. 



Before proceeding to take note of the other portions of the appen- 

 dicular skeleton, I introduce the subjoined tabular data of admea- 

 surements and proportions. Besides the two sexes of the Formosan 

 species, I have added for comparison that of a Rhesus, typical of 

 * P. Z. S. 1865, p. 562, " The Axial Skeleton of the Primates!" 



