492 Mr. J. Wood on Variations in Human Myology, [June 18^ 



rectus, and formed a muscle 2 inches wide, while passing upwards and 

 outwards across the axillary space, below and quite distinct from the 

 pectorals, to be inserted by a broad tendinous expansion into the fascia 

 covering the origin of the coraco-hrachialis muscle as high up as the coracoid 

 process. The pectoralis minor muscle was also very large and divided, 

 and altogether the arrangem.ent of these muscles resembled much that 

 found in the FelidcE and Rodents. The chondro- coracoid portion forms, 

 in the Norway Rat and Rabbit, a separate element distinct from the other 

 pectorals. It seems to be an upward transition of the insertion of the 

 epigastric slip above described, with which it coincides closely at its origin. 

 In animals it is considered by some writers a part of the panniculus 

 carnosus. 



In 4 male subjects the clavicular fibres of the pectoralis major were 

 fused with those of the deltoid, leaving only a small opening below for 

 the cephalic vein. This arrangement has been recorded by Otto as an 

 absence of the clavicular fibres of the deltoid, and by Seller as an origin 

 of the deltoid from the whole of the clavicle (Observ. xlnat. 1808, fasc. i.). 

 It indicates that kind of blending of the clavicular elevators of the upper 

 arm which reaches its highest form in the lower portion of the cephalo- 

 humeral muscle of the Carnivora and Rodents. 



In the female (No. 20) the clavicular fibres of the pectoralis were split 

 into two distinct muscles, one occupying the sternal, and the other the 

 middle third of the bone. They were united at their insertion only. 



10. Pectoralis minor. — In no less than 8 subjects, 4 male and 4 female, 

 in 7 on both sides, and in 1 (male) 

 on the left side only, a portion of 

 the tendon of this muscle, usually 

 the upper part, was prolonged 

 over a pulley-like groove upon the 

 coracoid process, and pierced the 

 coraco-acromial ligament to be con- 

 nected with the tendon of the su- 

 praspinatus muscle, and implanted 

 with it into the capsular ligament 

 of the shoulder-joint. In 2 of the 

 males (Nos. 10 & 12) the tendon 

 was also connected with the upper 

 fibres of the glenoid ligament at its 

 point of union with the capsular. 

 In No. 10 the pectoralis minor was 

 arranged in the complex manner 

 shown in fig. 4. The fibres of 

 the upper digitation {a), arising 

 from the second rib and intercostal 

 fascia, were joined to a roundish 



Fig. 4 (Subject No. 10). 



