FORE-LIMB. 133* 



monkeys whose arms are mainly used for prehension, show a 

 marked development of the extensor antebrachii group. 

 The following features are of interest, particularly in their 

 relation to the Anthropomorpha : The latissimus dorsi is 

 united with the teres major hefore its insertion. The dorso- 

 epitrochlearis is large. A coraco-brachialis hrevis is present 

 (a fairly constant muscle in Cynomorpha, hut usually absent 

 in Anthropomorpha). The three parts of the deltoid are 

 very distinct, leaving a considerable gap between the 

 acromial and spinal portions. The epitrochleo-anconeus 

 is well-developed. Palmaris longus fairly strong. There 

 is no extensor pollicis brevis. 0. C. 64 D. 



Champneys, Jour. Anat. & Physiol., vol. vi. 1871, p. 178. 



C. 161. Right fore-limb of a Crested Baboon (Cynopitliecus 

 niger), showing the dorso-epitrochlearis, coraco-brachialis 

 (brevis and medius), and brachialis internus muscles. 

 O.C. 64M&d. 



C. 162. Right fore-limb of Macacus maurus showing the muscles. 

 As a whole they do not display the powerful development 

 of the Baboon (C. 160), but in their details the two limbs 

 are closely similar. In addition to the features pointed 

 out in connection with the Baboon, it may be noted that 

 the deltoid is not separated into its three divisions and the 

 pronator teres is inserted somewhat lower down the radius. 

 Blue rods have been placed beneath the coraco-brachialis 

 brevis, extensor profundus, and the extensor digitorum 

 lateralis. The latter sends tendons to both iv. dig. and v. dig. 

 (this is general in Orangs, Gibbons, and Cynomorpha). 

 0. C. 64 Ma. Presented l>y J. Abrahams, Esq. 



Haughton, Proc. Irish Acad., vol. ix. 1867, p. 283. 



C. 163. Right arm and half the chest- wall of a Gibbon (Hylobates 

 leuciscus), showing the superficial muscles. In this essen- 

 tially arboreal anthropoid, the flexors of the elbow greatly 

 exceed the extensors in size and strength, but the 

 disproportion is not carried to the fore-arm as in the 

 Sloth (C. 146). The following details are noteworthy in 

 comparison with other Anthropoids. The deltoid extends 

 more than halfway down the humerus. The supinator 



