MUSCULAR SYSTEM OF MAMMALIA. 



5.5 



2:5 



Figures 23 and 24 give a view of the superficial muscles and 

 tendons of the fore-arm and hand of a full-grown male Gorilla and 

 Man of correct relative size. The portion 

 of the triceps is seen in the Gorilla at 2" ; 

 in Man at 5', in whom the origins of the 

 carneous fibres of that part from behind the 

 inter-muscular septum are continued lower 

 down the humerus. The ' brachialis anticus ' 

 is seen at 4, fig. 23, and 17, fig. 24. This 

 muscle is not so completely differentiated 

 from the deltoid and supinator longus in 

 the Gorilla as in Man, nor so individualised 

 as a single muscle : its two portions being 

 more distinct. The biceps, fig. 23, 3, 

 maintains in Man more of its full fleshy 

 character to the sending off of the tendon, 

 3', to the rough posterior margin of the 

 tuberosity of the radius, gliding over the 

 anterior smooth surface of that process with 

 an intervening ' bursa.' The aponeurosis, 

 3", sent off to the fascia of the fore-arm 

 crosses the 6 pronator teres.' This muscle, 

 8, fig. 24, is attached to the outer side of 

 the radius below the middle of the bone in 

 the Gorilla, but rather above it in Man. 

 The double origin, viz. from the inner 

 humeral condyle and the coronoid process of 

 the ulna, is better defined in Man, fig. 23, e. 

 The ' palmaris longus,' fig. 23, 8, arising 

 as a distinct muscle in Man from the inner IT 

 humeral condyle, is a fasciculus, 5, of the 

 'flexor carpi ulnaris ' (3, fig. 24) in the 

 Gorilla ; but, as this muscle is subject to 

 variation, and sometimes absent in Man, it 

 may show analogous inconstancy in the Go- 

 rilla. The flexor carpi ulnaris is inserted into 



the pisiforme in both Man and Ape, but the Muscles of the fore-arm and hand, 



fleshy and tendinous parts are better defined, 



and the latter relatively longer and more slender in Man, fig. 23, 9. 

 The flexor carpi radialis arises in Man, fig. 23, 7, from the inner 

 condyle, from the antibrachial fascia and septa continued there- 

 from between the pronator teres, 6, and palmaris longus, 8 ; but 

 in the Gorilla, fig. 24, 4, it derives a considerable accession of 



V. 



