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DBS. A. CAETE AND A. MACALISTEE ON THE 
of the scapula ; the fibres passed downwards, forwards, and outwards, and were inserted 
into the anterior and internal surface of the neck of the humerus ; some of the fibres 
were inseparably connected at their origin with the insertion of the serratus magnus. 
Supraspinatus. — This muscle lay immediately beneath the deltoid ; it arose from the 
upper border of the dorsum of the scapula and acromion process. The fibres ran 
downwards and backwards, converging to form a large triangular muscle, about half the 
size of the deltoid, and soon ended in a tendon, which was inserted into a ridge on the 
anterior inferior and external surface of the head of the humerus. 
Infraspinatus. — A large flat triangular muscle, arose fleshy from the lower half of 
the dorsum of the scapula ; its fibres passed upwards and outwards, and were inserted 
into the superior and external part of the head of the humerus. 
Subscapularis, also large and triangular, with its base towards the vertebral border of 
the scapula ; it arose from the entire subscapular fossa, and its fibres passed downwards, 
converging to form a flat tendon, which was inserted into the front of the head of the 
humerus superior to the humeromastoid muscle, which latter at this point formed a 
round tendon that lay in a groove in the head of the humerus. This muscle exhibited 
very few and indistinct tendinous intersections, thereby contrasting in a striking manner 
with the corresponding muscle in Globiocephalus Svineval , in which there were eight 
radiating tendinous plates running nearly parallel and partitioning the muscle into nine 
fleshy slips, which ended in a tendon that did not pierce the capsule of the scapulo-humeral 
articulation. 
The axillary vessels and nerves passed in front of the subscapularis tendon ; and the 
artery, which in this situation was of about the size of the human popliteal, had two 
venae comites accompanying it, and bifurcated at the lower border of the tendon, where 
it sent one branch, about the calibre of the human radial, down along the humerus, and 
the other (the subscapular) ran along the inferior border of the scapula. The brachial 
plexus of nerves was composed of very small branches, which broke up into muscular 
and cutaneous filaments. The plexus itself, prior to its division, lay on a plane superior 
and external to the vessels. 
At the upper part of the axillary space two remarkable series of veins were situated, 
one set being placed anterior and horizontal, the second set posterior and vertical ; the 
former was contained in a flat and membranous expansion, and was somewhat quadri- 
lateral in outline ; the vessels composing it, with the exception of a few intercommuni- 
cating branches, ran parallel to each other, and were held together by a strong cellular 
investing membrane. This plexus was situated above the subscapularis and posterior to 
the origin of the omohyoid muscle. 
The second, or vertical plexus, lay about 2 inches posterior to that just described ; it 
was flat and triangular in outline, with its apex, which was thin and membranous, directed 
towards the vertebral column ; its base or inferior border, enclosing the second series of 
vessels, was formed of dense cellular tissue, and presented a well-defined border, which ex- 
. tended from the first rib, internally, to the apex of the shoulder on the external or pectoral 
