MUSCLES OF THE FORE LIMB 87 



head being in some of these birds entirely diverted to form 

 the biceps slip to the patagialis (q.v.) The coracoidal head, 

 when it exists alone, may be divided into two quite separate 

 muscles, uniting only at their very origin. This is the case 

 with certain Alcidae. This division of the coracoidal half of 

 the muscle also exists in the Laridae and in certain Limicolae, 

 where there is a humeral head present also. In the Stega- 

 nopodes both heads are present, but the humeral head after 

 its attachment to humerus is continued on to the coracoid. 

 A. trace of this arrangement is apparently left in some birds 

 (e.g. Porpliyrio), where, though the humeral head arises from 

 the humerus only, a ligament passes on from that part to 

 the coracoid. 



Brachialis Inferior. A flat fleshy muscle arising from 

 the distal part of the humerus, and inserted upon the ulna. 

 In the penguins (where the biceps is absent) this muscle is 

 particularly large, and is inserted on to the radius. 



PronatorSnblimis. This muscle springs tendinously from 

 the inner condyle of the humerus and is inserted fleshily, 

 and for a varying distance in various birds, upon the second 

 third to second eighth of the radius. 



Pronator Pro/Hindus.- This muscle lies deep of the last, 

 but has a similar origin and insertion. In the Katita3 this 

 muscle and the last form a single muscle. 



Entepicondylo-ulnaris. This muscle, found apparently 

 only in Galli and Tinami, arises in common with the pro- 

 nator profundus, and is inserted on to the ulna. 



Ectepicondylo-radialis. This muscle arises tendinously 

 from the outer condyle of the humerus and is inserted 

 fleshily on to the radius. It appears to be wanting in the 

 penguins, and to be largest in the Galli. 



Ectepicondylo-ulnaris. This muscle arises from the 

 outer condyle of the humerus, and is inserted similarly to 

 the last upon the ulna. Its insertion is fleshy, and in 

 Palamedea it is larger than the last. 



Flexor Carpi Ulna-ris. This arises from the inner con- 

 dyle of the humerus by a strong tendon, in which there is 

 a well-marked sesamoid ; it runs down the inner side of the 



