MACALISTER — ON THE MUSCLES IN CERTAIN MONKEYS. '.'j7 



was inseparable from the subscapular muscle. This muscle I have seen 

 very large and distinct in Rhesus and several other species of Simiadac. 

 The extensor ossis metacarpi pollicis was very large, and the extensor 

 primi internodii was obsolete. The same condition I have found in Ma- 

 cacus nemestrinus and Sinicus. A very common arrangement in mon- 

 keys seems to be the fusion of the extensor ossis metacarpi and of the 

 primi internodii pollicis, forming a single belly, from which two tendons 

 are detached. 



In the lower extremity the gluta3us medius and the pyriformis were 

 inseparably united together — an interesting variety, as it is a rare occur- 

 rence in human anatomy. The gemellus inferior was vertically doubled ; 

 and lower down there existed an extensor ossis metatarsi hallucis, se- 

 parate from the well-developed extensor proprius hallucis, which ex- 

 tended down to the second phalanx. 



A peronseus quinque was present as a separate muscle, arising from 

 the fibula, under cover of the peronaaus brevis, but neither peronseus 

 tertius nor quartus was to be seen. 



In a Cercopitkecus ruber there existed a distinct opponens pollicis 

 for each thumb ; but there was not any long flexor tendon for that mem- 

 ber, either separate or even derived from the common deep flexor of the 

 fingers. The short flexor was short and thick. In this animal, like- 

 wise, a slip passed from the posterior fibres of the deltoid to join the long 

 head of the triceps. 



In the lower extremity of this species there was no plantaris. A 

 peronseus quinque arose from the peronseus brevis, and there was deve- 

 loped an extensor ossis metatarsi hallucis, without any extensor for 

 the first or second phalanx of the great toe, the flexor for which was 

 present as usual. 



In a Macacus Sinicus I found the peculiar arrangement of the di- 

 gastrics which characterizes many of the Quadrumana — namely, a union 

 of the anterior bellies of each side. The mode in which this occurred 

 was interesting, as the tendon of the posterior belly was continued as a 

 species of sling from one muscle to the other across the median line, 

 and from this the fibres of the anterior belly arose, and ran directly 

 forwards to the chin ; other species of this genus present the same ar- 

 rangement and so does Inuus. In this animal likewise I found the 

 coraco-capsular slip before alluded to, and a very distinct opponens 

 pollicis. The long flexor tendon for the thumb differed from that of 

 Cebus in arising, not from the outer side, but from the middle of the 

 flexor profundus tendon ; and, as it crosses over the slip of the latter for 

 the index finger, this somewhat reminds us of the arrangement of the 

 flexor tendons in the human foot. The same mode of attachment ob- 

 tains in Ehesus, and Mivart* mentions a similar arrangement in Cerco- 

 pitkecus sabceus. The infraspinatus secundus was large, but connected 

 to the subcapsular muscle. The flexor digitorum profundus prc- 



* Op. cit., p. 44. 



