698 



ME. T. MANNERS-SMITH ON* THE 



[Dec. 4, 



and are inserted into the radius at the junction of the upper and 

 middle thirds. Between the two heads of origin a muscle is 

 inserted which is probably the pectoralis minor. Only one head 

 is present in Echidna (Mivart, loc. cit.). 



Fig. 1. 



a. Brachialis anticus. 



Muscles of Akm. 



(3. Triceps, 

 brachialis. 



y. Infra-spinatus. 

 e. Deltoid. 



o. Epicoraco- 



Coraco-hrachialis. — Two portions of the typical coraco-brachialis 

 are present. A longer superficial portion, arising in conjunction 

 with inner (larger) head of biceps from sternal portion of coracoid ; 

 it is inserted into the bar of bone bridging over the well-marked 

 supra-condyloid foramen. The deeper portion arises from coracoid 

 and whole of epicoracoid, just below and in front of glenoid 

 cavity ; it is inserted into the upper third of the humerus. The 

 two portions are entirely distinct, the tendon of latissimus dorsi 

 separating them from below ; both parts are supplied by a branch 

 from the median nerve. The first portion only is called by Coues 

 coraco-brachialis ; the second he describes as epicoraco-brachialis ; 

 the same two portions are found in Echidna (Mivart, loc. cit.). 

 There is a distinct epicoraco-brachialis, but in addition two 

 portions of the typical coraco-brachialis are present, as described 

 above. 



BracMcdis anticus. — Arises from humerus, its origin extending 

 as high as the head of the bone. The muscle is inserted into the 

 upper fourth of the shaft of the ulna. 



Triceps. — This is a very large, strong muscle, consisting of four 



