BY \V. J. S. McKAY. 293 



Insertion. Running forwards and slightly inwards the 

 muscle is inserted on the postero-internal portion of the dorsal 

 surface of the epicoracoid. 



Relations. The muscle, as in Echidna, lies in a plane 

 dorsal to the costo-coracoid, and hides from view the inner part of 

 that muscle. At its insertion its external border is closely related 

 to the origin of the epicoraco-brachialis and insertion of the costo- 

 coracoid. 



Innervation. Echidna ; iv. et v. cervical nerves. Orni- 

 thorhynchus ; iv. et v, et vi. cervical nerves. 



Westling — Echidna : Nn. thoracici anteriores, from v. et vi. 

 cervical nerves : Ornithorhynchus, N. subclavius, from v. et (vi.?) 

 cervical nerves. (Fig. 17, Scl.). 



Echidna. 



Westling says : — " M. costo-coracoideus (Fiirbringer) is fan- 

 shaped and arises fleshy from almost the whole anterior border of 

 the first rib ; its fibres converge to a tuberosity on the hinder part 

 of the dorsal face of the coracoid, on which it is inserted closely 

 connected with the M. coraco-brachialis." Westling then remarks 

 — " Nach Fiirbringer kann man diesen Muskel sowohl mit dem 

 gleich-benannten beim Krokodile als auch mit dem M. subclavius 

 der hohern Siiugethiere vergleichen." 



Of the M. sterno-coracoideus (Fiirbringer), Westling says, it 

 arises from the dorsal face of the manubrium sterni and the 

 sternal end of the first rib, and is inserted on to the dorsal face of 

 the epicoracoid, " medial" from the origin of the epicoraco-brachial. 

 Westling remarks — " Dieser Muskel steht wie der vorhergehende 

 in naherer Beziehung zu dem M. subclavius der Maisupialien und 

 Placentalien, und ist auch bei den meisten Sauriern gut entwickelt" 

 (and refers to Fiirbringer). 



Leche follows Westling. 



MiVART says — " I could find no muscle evidently representing 

 a pectoralis minor ; but there is a small and thin muscle which 

 arises from the anterior border of the first rib for the greater part 

 of its length, and which is inserted into the coracoid immediately 



