306 



THE MUSCLES. 



Form, Structure, and Attachments of the muscular portion. — It presents a band 

 elongated from before to behind, extending from the sternum to the transverse 

 processes of the last lumbar vertebrae, following in its course the direction of the 

 cartilages of the ribs, and composed of parallel fibres passing from one border to 

 the other. 



Its superior border, concave, is attached : 1. To the internal surface of the 

 asternal ribs by digitations placed opposite those of the diaphragm, but the 



Fig. 177. 



MUSCLES OF THE ANTERIOR ASPECT OF THE BODY OF MAN. ON THE LEFT SIDE THE SUPERFICIAL 

 LAYER IS SEEN ; ON THE RIGHT, THE DEEPER LAYER. 



1, Pectoralis major ; 2, deltoid ; 3, anterior border of the latissimus dorsi ; 4, serratus magniie ; 

 5, subclavius, right side ; 6, pectoralis minor ; 7, coraco-brachialis ; 8, biceps, with its two heads; 

 9, coracoid process of the scapula; 10, serratus magnus, right side; 11, external intercostal 

 muscle of the fifth intercostal space; 12, external oblique; 13, its aponeurosis with the linea 

 alba; 14, Poupart's ligament; 15, external abdominal ring; 16, rectus muscle of right side; 

 17, pyramidalis muscle; 18, internal oblique; 19, conjoined tendon of internal oblique muscle 

 and Poupart's ligament. 



majority of which do not mix with them. 2. To the extremity of the transverse 

 processes of the lumbar region by a thin fibrous layer. Its inferior border is 

 convex, and continuous with the aponeurosis. 



Form, Structure, and Attachments of the aponeurosis. — This is triangular- 

 shaped, with the base behind, and with its fibres running in a direction trans- 

 verse to the median line. Closely laid one against another in front, these fibres 

 separate behind, and form only a very thin and incomplete layer. 



By its external border, the aponeurosis is joined to the inferior margin of 



