THE MUSCLES OF THE UPPER EXTREMITY. 75 



pectoral group of muscles, and is found to the outer side 

 of the one last described. As with the first two, its 

 fibres arise fleshy, and in its case, from an area occupy- 

 ing the anterior half (in length) of the outer moiety (in 

 width) of the pectoral aspect of the body of the sternum, 

 including the broad costal process where it is attached to 

 the fascia of the suhclavius muscle which lies beneath it. 

 It also arises from the outer lower third of the 

 corresponding coracoid process, which latter area lies in 

 close juxtaposition with the somewhat similar origin of 

 the second pectoral (Figs. 24 and 25). From these 

 two origins the fibres of the muscle converge as they 

 ascend upwards, pass to the outer side of the coracoid 

 bone, and as they approach the humerus they become 



Pectoralis tertius. Schijpss, p. 113, No. 16. 



Coraco-brachialis s. Pectoralis tertius s. minor. Rudinger, p. 80. 



Coraco-brachialis. Reid, p. 141 ; Gei-vais et Alix, p. 23 ; Alix, p. 393. 



Suhclavius. Retzius. 



Pectoralis minor s. tertius. Owen, Apteryx, p. 289. 



Coraco-brac/iialis longvs. Selenka, p. 114, No. 40 ; De Man, 



p. 106 ; Carlsson, p. 26. 

 Coraco-brachialis internus. Furbringer, Morph. Jahrb. v. 

 Pectoralis minor. Watson, p. 83. 

 Coracobracldalis posterior s. internus. Furbringer, Monographic." 



Valuable observations are passed upon this muscle by the writer 

 just quoted in the same connection, and he, after dwelling upon its 

 anatomy in a number (if bird-groups, declares that, " Er entspricht 

 nicht dem M. coraco-brachialis des Menschen, der vom Proc. cora- 

 coideus zum Schafte des Humerus geht. Besser zu vergleichen ist 

 er einem zweiten 31. coraco-brachialis, der bei vielen Saugethieren 

 sich am Tuberc. int. humeri besfestigt und bei den Monotremen, die 

 ein Sauropsiden ahnliches Coracoid besitzen, sehr stark und 

 vogelahnlich entwickelt ist. Dass er nicht als ein Pectoralis 

 mi7ior, soudern als Corac. brachial, aufzufassen ist, hat Selenka 

 (Literatur, No. 121) ausgefuhrt. Bei den Amphibien und Rep- 

 tilien ist er in dem ebenfalls als Coraco-brachialis beschriebcnen 

 Muskel zu erkennen" {Joe. cit., p. 2.53). 



