336 MESSRS. MURIE AND MIVART ON THE [Apr. 11, 
thickness in the pectoral region. Its attachments are the median 
line of the back, the median line of the abdomen, anteriorly and 
above to the fascia covering the scapula. Anteriorly below (where 
the muscle is thicker) it divides into two separate layers, the deep 
and much narrower one being inserted into the lesser tuberosity of 
the humerus, and so intimately connected with the insertion of the 
pectoralis minor as to be readily confounded with it. The more 
superficial portion, with its antero-posteriorly directed fibres, covering 
the front of the thorax, fixes itself so as to be in a manner fused 
with the obliquely directed fibres of the pectoralis minor at the 
posterior border of that muscle. The outer portion of this super- 
ficial layer, however, terminates in a slip, which bifurcates, one part 
being attached to the fascia covering the biceps in common with a 
portion of the latissimus dorsi, as above described, the other part 
being inserted into the inner margin of the bicipital groove of the 
humerus, in common with the teres major and other portion of 
the latissimus dorsi (see fig. 4, P.c.). The fibres of the posterior 
part of this muscle (the panniculus carnosus) converge from the back 
opposite the ilium, and from the lower portion of the abdomen, to 
form a pyramidal fasciculus, which passes to the lower limb, and is 
inserted into the superficial aponeurosis of the leg over the knee. 
Fig. 4. 
S.cl. m2 C. 
Muscles of the thoracic region. 
P. maj. Pectoralis major (cut through and turned back). P. min. Pectoralis 
minor. S.cl.m. 2. Sterno-mastoid, its second part. S. sc. Sterno-scapular. 
C.h. Cephalo-humeral. B. Biceps. 7.1. First portion of triceps. D.e. 
Dorso-epitrochlear. P,c. Panniculus carnosus. 
The external oblique is very long, considering the proportions of 
the animal. It arises from the whole of the ribs, except the three 
most anterior ones; Meckel* states, from all except the first five. 
Its other attachments are from the crest of the ilium and linea alba, 
* Loc. cit. p. 194. 
