BY W. J. S. McKAY. 303 



Ornittiorhynchds. 



OwEN" says, " there are also two muscles to which the niine 

 coraco-brachialis may be applied, a superior one and au inferior 

 one." 



CouES says — " Tvvo perfectly distinct muscles besides the one 

 above called anterior deltoid [epicoraco-humeral] proceed from the 

 coracoid opposite to the humerus ; they have together been con- 

 sidered as coraco-brachialis, Init the name is properly applicable 

 to only one of them." He then proceeds to describe the coraco- 

 brachialis proper. After this Coues describes the e|)icoraco- 

 brachialis: "^Nluch larger than the other and with different origin, 

 course, relations and insertions ; lying partly upon and partly 

 under the whole coracoid apparatus, and upon the posterior aspect 

 of the proximal moiety of the humerus. Viewed at first from the 

 outside, superficially, it appears to arise from the coracoid proper, 

 and to descend thence upon the humerus. But its real origin is 

 much more extensive, from the whole, or nearly all, of the under 

 (internal) surface of the epicoracoid lamella, as a thin expanded 

 sheet whose contour is determined by that of the bony plate just 

 named. It giins the outside by curving around the coracoid 

 proper, reminding one of the escape of the iliacus over the pelvic 

 brim, or of the obturator internus over the border of the ischium. 

 It has a broad fleshy insertion into the expanded surface of the 

 humerus, upon the aspect of that bone abov^e noted, as far down 

 as the insertion of the latissimus." 



Westlixg says that in the Ornithorhynchus, according to Coue.s, 

 the M. coraco-brachialis is only differentiated into two muscles, 

 and thatinSaurians there are a M. coraco-brachialis longus and a 

 brevis, whose origins and insertions are similar to those of the 

 Echidna. 



Leche says that in Orn'ithorhyncluis the epicoi'aco-brachialis 

 and coraco-brachialis brevis are blended into one strong muscle. 



Meckel — " Anterior, longe major, transversus, et a partis 

 scapulae coracoidete facie interna fere tota, nee non ab osse quadrato, 

 infra cavitatem scapulae glenoideam extrorsum tendit et infra 



