864 MR. ST. GEORGE MIVART ON THE [ Dec. 6, 
it is inserted into the anterior part of the outer surface of the 
scapula, near its summit, between tbe insertions of the levator 
claviculz and posterior suprascapular. 
Latissimus dorsi (figs. 1, 6,8, L. D). This rather large muscular 
sheet springs from the strong fascia which binds down the erector 
spinee, and from the vertebral portions of the third and fourth of 
those ribs which extend to the sternum. Its origin extends for- 
ward beneath the trapezius, which thus overlaps it. It is inserted 
into the ulnar side of the upper part of the humerus, a little distance 
below the insertion of the subscapularis. No tendon passes down on 
its inner side, as it does in the Iguana. 
Serratus magnus * (figs. 6, 7,8, & 13,8. MZ). This is much di- 
vided, consisting of one large and three smaller portions. The first 
springs from about the angles of the first three ribs which join the 
sternum, and is inserted into the posterior margin of the scapula. 
The other three parts spring, two from the first rib, and one from the 
second, above their angles, and are inserted into the inner side of the 
upper part of the scapula and into its posterior margin. 
Anterior suprascapular (figs. 1, 6, & 13, S'). A muscle which 
may perhaps be conveniently thus distinguished springs from the 
anterior part of the outside of the scapula, and is strongly inserted out- 
side the head of the humerus, behind the subclavius, and in front of 
the insertion of the deltoid. It has the levator clavicule and omo- 
hyoid in front, the posterior suprascapular behind. 
The posterior suprascapular + (figs. 1, 6, 13, S*) is a thick fleshy 
muscle, which arises from the posterior part of the outer side of the 
scapula, and is inserted into the humerus just above (behind when 
the humerus is vertical) the insertion of the deltoid. 
The deltoid appears to consist of two parts. The upper or pos- 
terior portion (tigs. 1, 6, 7, & 13, D") arises from the inner end of the 
ventral margin of the coracoid groove of the sternum, just external 
to the origin of the second part of the deltoid, and internal to and 
overlapped by the sterno-mastoid. Some fibres arise from the spur 
of the epicoracoid. Passing down superficially to the subclavius, it 
is inserted into the head of the humerus, between the insertions of 
the pectoralis and of the second part of the suprascapular. 
The second, lower or anterior part of the deltoid (figs. 1, 6, 7, & 
13, D®) arises from the innermost part of the ventral margin of the 
coracoid groove of the sternum, just within the origin of the first 
part of the deltoid. It is inserted into the humerus above the sum- 
mit of the brachialis anticus, and on the antero-inferior side of the 
insertion of the first part of the deltoid. It is superficial to part of 
the subclavius ; and its antero-inferior margin is conterminous with 
the upper border of the most anterior part of the pectoralis. 
Omo-hyoid. This muscle has been described amongst the others 
which belong to the hyoid. 
Subscapularis (fig. 8, S'& S*). This large muscle consists of two 
distinct parts. One arises from the whole costal surface of the ossi- 
fied part of the seapula, between the insertions of the levator clavi- 
* Meckel, 7. c. p. 313. + Meckel, 7c. p. 542. 
