196 MR. r. E. BEDDAED — CONTRIBUTIONS TO THE 



(38) Flexor hrevis hallucis arises from the cuboid bone by a short flat tendon ; it is 

 inserted by a single insertion, in common with the adductor hallucis, which is fleshy. 



(39) Adductor hallucis. — This is a strong fleshy muscle which arises partly from the 

 sheath of the peronceus longus, partly from the plantar fascia, and partly from the heads 

 of the metatarsals ; the muscle measures one inch in diameter at the middle ; it is 

 inserted in common with the fleshy flexor brevis on to the base of the first metacarpal. 



(40) A very small slender muscle arises by a tendon measuring half an inch in 

 length from the sheath of the peronceiis longus ; the delicate muscular belly in which 

 it ends measures 3 mm. in diameter and about an inch in length; it passes across 

 the transversus pedis in close connection with it, but I could not determine its insertion ; 

 I found this muscle only in one foot. 



(41) Transversus pedis is of some size; it arises from the metatarsal ligament of the 

 second, third, and fourth digits ; it is inserted on to the thumb in common with the 

 adductor hallucis. 



§ 8. Comparison of Musculature with that of the Common Chimpanzee. 

 In the following table the principal difl'erences between Troglodytes calvus and 

 Troglodytes niger are shown (according to Sutton's account of the myology of the 

 latter i) : — 



T. calvus. T. niger. 



Pect. minor Insertion : coracoid. Insertion : capsule of shoulder-joint. 



Biceps cruris Ischial head present. Ischial head absent. 



Soleus From head of fibula only. From upper third of posterior surface 



of fibula only. 



Flex. prof, digit Attached by a vinculum to No such vinculum " (?). 



Flex. long, digit. 



Flex. long, digit Supplies digits i., iv., v. Supplies digits ii., v. 



Lumbricales Tliree. Four. 



Flex. long, poll Well-developed ; supplies index Absent or feebly developed ; supplies 



and poUex. only pollex. 



E.vt. min. digit Absent. Present. 



Macalister ^ has noted that in the Chimpanzee the dorso-epitrochlear ended in a 

 fascia in the middle third of the arm ; it is thus more rudimentary than in Troglodytes 

 calvus. The flexores profundus and ■pollicis were found by Macalister to be fused into 

 a single muscle ; but the double condition shown in the Ape described in the present 



' Journ. Anat. & Phys. vol. xviii. p. 66 (1884). 



^ This vinculum, however, is stated by Macalister to occur. Sutton does not say it is absent ; he does not 

 refer to it. 



' " On some points in the Myology of the Chimpanzee and others of the Primates," Ann. & Mag. Nat. Hist, 

 vii. (1871) p. 341. 



