1892.] MUSCULAR ANATOMY OF AULACODUS. 521 



of the sterno-scapular ; these may possibly be regarded as being 

 collectively the equivalent of the pectoralis minor of other animals. 



Both Sterno-mastoid and Oleido-mastoid are present ; the latter is 

 of about half the size of the former and arises from the middle of 

 the clavicle. 



The Omohyoid is present and is large. 



The Levator claviculce is continuous with part of the panniculus 

 carnosus. 



The Latissimus dorsi is a large muscle and gives off a good-sized 

 dorso-epitrocJilear slip to the elbow ; the latter is 8 mm. across ; 

 the latissimus dorsi is inserted in common with the teres. 



The Trapezius is extensive ; it is continuous with part of the 

 panniculus, but its strong tendon can be seen to be separate. 



The Rhomboideus is attached along the whole length of the 

 vertebral border of the scapula and also ventrally to the fascia 

 covering the supra-spinatus and to the spine of the scapula itself, 

 just at the point where the spine ends in the vertebral border of the 

 scapula. 



The Sterno-scapular is in two parts : the shorter and narrower 

 part arises from the sternum and from the cartilage of the first rib ; 

 it is about 5 mm. across near to its origin ; at the insertion it splits 

 into two parts — one entirely muscular, the other nearly entirely 

 tendinous ; the former joins the fourth part of the pectoralis, the 

 latter becomes continuous with the second and larger half of the 

 sterno-scapular. 



The Deltoid is a double muscle : one part arises from the clavicle, 

 the other from the metacromion ; they are inserted together above and 

 to the outside of the insertion of the pectoralis to the deltoid ridge. 



The Biceps is double-headed ; the short head arises in common 

 with the coraco-brachialis. 



The Coraco-brachialis is a single muscle ; its insertion extends 

 7 mm. beyond the insertion of the ieres. 



The Brachialis anticus has two heads of origin. 



The Triceps is, as usual, a very massive muscle ; the scapular 

 head is the largest, and arises also partly from the fascia covering 

 the infraspinatus. 



The Teres major ends in a flat tendon, 9 mm. across, which is, as 

 has already been mentioned, inserted in common with the latissimus 

 dorsi. 



The Subscapularis commences about 12 mm. away from the 

 vertebral border of the scapula. 



The Pronator radii teres is inserted on to the middle of the shaft 

 of the radius ; the half nearest to the insertion has a glistening 

 tendinous surface. 



The Flexor carpi radialis arises from the flexor condyle of 

 the humerus ; its tendon begins 30 mm. from the origin. 



The Flexor carpi ulnaris is a large muscle ; the tendon, which is 

 broad and strap-shaped, is the widest of all the flexor tendons. 



The Flexor sublimis arises from the flexor condvle and from the sep- 

 tum between itself and ih&jlexor profundus ; it receives an excessively 



