1S90.] HELODERMA SUSPECTUM. 167 



is here divided into two parts : the most posterior part envelops the 

 hinder border of the scapula and suprascapula in a deshy mass, en- 

 croaching slightly upon tlie adjacent surface of the coracoid. After 

 this it converges to form rather a strong tendon, wliich is subse- 

 quently joined by the weaker tendon from the second part. This 

 latter arises from the inner surface of the corresponding coracoid, 

 covering a longitudinally-placed, elliptical area, occupying the 

 greater share of its lower third. As already intimated, its tendon 

 joins the tendon of the first part, just beyond the border of the 

 coracoid, when almost immediately they become inserted into the 

 distal margin of the head of the humerus at its posterior aspect. 

 Between these two divisions of the subscapularis, the sternocosto- 

 scapularis muscle is inserted, upon the mesial aspect of the shoulder- 

 blade. Externally, the subscapularis covers by its origin about half 

 of the scapula, extending but very slightly upon the suprascapula, 

 and in this locality is covered for its anterior portion by the infra- 

 spinatus. Just before inserting its tendon upon the humerus, a 

 portion of the former is deflected and so expanded as to become in- 

 serted into the juxtaposed capsular ligament of the shoulder-joint, 

 and this part of the insertion of the subscapularis seems to be en- 

 joyed by the muscle among most Lizards. 



FUrbringer and Hoffmann term this muscle the subcoracoscapularis, 

 but the name I here adopt for it is the one that has been used by 

 Mivart, Sanders, Stannius, Pfeiflfer, Riidinger, and other anatomists. 

 31. The Biceps here arises but by a single tendon, of some 

 considerable width, which has its origin upon the external surface 

 of the coracoid of the same side, it being limited to a curved line 

 on the posterior moiety of the bone immediately within the line of 

 the sterno-coracoidal articulation. The muscle passes directly down 

 to a point just in front of the elbow-joint. It is not until it gets 

 opposite the head of the humerus, however, that the thin flat tendon 

 of the biceps becomes carneous, and even here it does not show 

 any disposition, as it does nowhere else throughout its extent, to 

 divide so as to exhibit anything that might be compared to two 

 heads. At the middle of the brachium the muscle is considerably 

 beUied and fleshy. Opposite the elbow-joint it again becomes 

 tendinous, and its tendon here is transversely disposed, binds down 

 the anterior aspect of the brachialis anticus muscle, as it spans the 

 interosseous space, and finally is inserted into both the ulna and 

 the radius, the ulnar insertion being much the stronger of the two. 



Sanders found that the biceps is only represented by its coracoidal 

 head in Liolepis, while Mivart found that in Parson's Chamseleon 

 its insertional slips arched over the brachialis anticus muscle, ex- 

 posing the latter to view in front, and he says of it, that "Descend- 

 ing in irout of the insertion of the pectoralis, it there becomes fleshy, 

 and becomes more or less divisible into two bellies, which embrace 

 the brachialis anticus in front, but leave part of the latter visible 

 within and without the arm." As I have just said, here in 

 Heloderma it covers the brachialis anticus, and simply spans the 

 interosseous space in front of it as it makes its double insertion, 



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