1895. | NEW YORK ACADEMY OF SCIENCES. 259d 
ing the Coraco-brachialis to a deep ventro-appendicular muscle 
confined in its insertion to the humerus. 
It is only in the Third Internal humeral head of the Biceps, 
and in the Coraco-epitrochlear slips, that we still find the evi- 
dence of the original connection between these muscles, and see 
the reversion of the Biceps toward its lost ulnar segment. 
It is only necessary to refer in this connection to the interest- 
ing account of the structure of the Coraco-brachialis given by 
Prof. Wood,* and to point out the significance of the occasional 
Coraco-brachialis longus. 
Analysis of cases of Quadriceps flexor cubiti and evidences 
of the ulnar tendency of the Biceps in variations of the insertion. 
In the above series five examples of a four-headed muscle 
have been encountered. 
l. ¢, Ireland, aet. 45. January 9, 1894. 
Plate XL. Right upper extremity. 
A third additional head (gleno-ulnar) arises by a flat tendon 
from the capsule of the shoulder-joint, between the long and 
coracoid heads. It is separated above from the main muscle by 
the muscuto-cutaneous nerve, after the latter has perforated the 
Coraco-brachialis. A fourth additional head (coraco-ulnar) 
arises from the inner surface of the shaft of fhe humerus, almost 
directly continuous with the Coraco-brachialis at its insertion, 
and separated from the Brachialis anticus by a branch to the lat- 
ter muscle from the musculo-cutaneous nerve. 
The left upper extremity of the same subject presents the addi- 
tional internal humeral head from the Coraco-brachial insertion. 
The case affords an example of the typical composition of the 
four-headed muscle. The gleno-ulnar head passes to the deep 
and ulnar surface of the main muscle, which is joined lower down 
by the coraco-ulnar, the continuity of the latter with the Coraco- 
brachialis being well marked. The superficial part of the muscle 
is constituted by the large gleno- and coraco-radial heads. 
2. 9, Ireland, aet 40. October 25, 1894. 
Plate XLI. Both upper extremities present the same ar- 
rangement. 
A third anomalous head arises from the glenoid margin and 
capsule of the shoulder, passes down over the bicipital groove, 
covering the tendon of the long head, supplied by a branch from 
the musculo-cutaneous nerve, ‘after the same has perforated the 
Coraco-brachialis. A fourth additional head arises from the 
humerus, along the outer margin of the tendinous Coraco-brach- 
ialis insertion. 
The main portion of the musculo-cutaneous nerve, after per- 
* Journal of Anatomy and Physiology, Vol. I., p. 44, 1867. 
