IIS SCHULTE, SEI WHALE. 



very strong ligamentous bands; the larger is. continued in the line of the tendon along the 

 venter of the humerus to the capsule of the elbow joint and the proximal portion of the radius; 

 the smaller takes a slightly oblique course to the ulnar aspect of the elbow passing laterad of the 

 insertion of the coraco-brachialis, latissimus and teres. In these bands it is possible to see the 

 rudiments of the long and short heads of the biceps. Carte and McAlister mention tendinous 

 bands on the flexor surface of the humerus in B. rostrata ( B. acuto-rostrata) , which they too 

 take to be rudiments of the biceps. For the rest their account of the muscules of this group 

 differs materially from the foregoing. They describe a masto-humeral with additional origins 

 from the transverse processes of the anterior cervical vertebrae. This they found inserting 

 into the anterior and internal part of the humerus. They do not mention a trapezius (cephalo- 

 humeralis) nor a cleido-mastoid. Their sterno-mastoid has an additional head from the first 

 and second costal cartilages. This last point of difference is probably due to their failure to 

 distinguish the sterno-mandibularis which in B. borealis has a costal origin and immediately 

 overlies the sterno-mastoid. 



Ventro-appendicular musculature. The pectoralis is an extensive sheet of muscle which 

 covers the venter of the thorax and extends upon the abdomen to within 1.5 cm. of the umbili- 

 cus. It arises from the ventral surface of the sternum, from the whole width of the first rib 

 by a narrow origin between the attachments of the rectus and of the external oblique, and 

 extensively from the linea alba. Here while it approaches its fellow of the opposite side very 

 closely, I was not able to detect an interdigitation of the fasciculi of the two muscules. The 

 fasciculi are directed in the main transversely with a slight inclination cephalad to an exten- 

 sive insertion into the lateral raphe" and the aponeurosis which invests the humerus, only a 

 minority of its fasciculi inserting into the preaxial border of that bone under cover of the 

 deltoid. In the raphe the pectoralis is united with the ventral and dorsal divisions of the pan- 

 niculus and with the latissimus dorsi, and retains this relation to the ventral panniculus in its 

 insertion into the aponeurosis of the arm. Its pannicular affinities are further indicated by its 

 innervation from branches of the long thoracic. Throughout the whole sheet the course of 

 the fasciculi are parallel, there is no convergence towards the shoulder, and the thoracic portion 

 of the muscle is distinguished from the abdominal by its greater thickness alone. There is 

 no pectoralis minor. 



The latissimus dorsi is a small thin muscle parallel to the caudal margin of the scapula. 

 It arises from the aponeurosis covering the dorsal extensor muscles and on its deep surface it 

 is reinforced by delicate slips from the 7th, 8th and 9th ribs. Its fasciculi converge somewhat 

 to their insertion being directed rostro-ventrad to the lateral raphe where they meet those of 

 the pectoralis, and to the flexor surface of the humerus where they are inserted ventral to the 

 subscapularis and teres. With the tendon of the last the latissimus is intimately joined as it 

 crosses its ventral surface to gain a proximal insertion upon the humerus. The nerve supply 

 is by a slender branch of the long thoracic which lies upon the ental surface of the muscle and 

 penetrates it near its middle. 



The coraco-brachialis is placed on the ventro-mesial aspect of the shoulder. It arises 

 from the tip of the coracoid process and crossing the tendon of the subscapularis is inserted into 

 the humerus immediately below the head and just mesial to the ligamentous bands, which are 

 probably representative of the biceps, with the postaxial one of which it is connected by a narrow 

 slip as Perrin found. 



