THE VENTRAL MUSCLES. 



519 



3. Cremaster (Figs. 525, 167 1), 



Attachments. — The cremaster muscle consists of a series of somewhat scat- 

 tered loops of muscle-tissue derivied from the lower part of the internal oblique and 

 to a slight extent from the transversalis. It is attached laterally to Poupart's liga- 

 ment and medially to the anterior layer of the sheath of the rectus. The loops de- 

 scend through the inguinal canal along with the spermatic cord, the muscle being 



Fig. 525. 



Serratus magnus 



Latissimus dorsi 



Edge of cut external oblique 



Internal oblique 



Posterior aponeurosis of internal 

 oblique 



Iliac crest 

 Fascia lata 



Cut edge of fascia lata 

 Gluteus maximus 



Pectoralis major 



Edge of cut aponeurosis of 

 external oblique 



— Linea alba 



Anterior aponeurosis of interna] 

 oblique 



Anterior superior iliac spine 



Conjoined tendon 



Suspensory ligament 

 Cremaster fibres 



Dissection of lateral body-wall, showing internal oblique muscle. 



well developed only in the male, and spread out in the tunica vaginalis communis of 

 the testis and spermatic cord. The loops are united by connective tissue which forms 

 part of the cremasteric fascia. 



Nerve-Supply. — By the genital branch of the genito-crural nerve. 



Action. — To draw the testis upward towards the external abdominal ring. 



4. Transversalis (Fig. 526). 



Attachments. — The transversalis (m. transversus abdominis) is the deepest 

 layer of muscle on the lateral abdominal wall and immediately underlies the internal 

 oblique. It arises from the cartilages of the lower six ribs, from the lumbo-dorsal 



