OF THE ABDOMEN. 



451 



muscle which is reflected downward and outward from the spine of the os pubis 

 to be inserted into the pectineal line. It is about half an inch in length, larger 

 in the male than in the female, almost horizontal in direction in the erect 

 posture, and of a triangular form with the base directed outward. Its base, 

 or outer margin, is concave, thin, and sharp, and lies in contact with the crural 

 sheath. Its apex corresponds to the spine of the os pubis. Its posterior margin 

 is attached to the pectineal line, and is continuous with the pubic portion of the 

 fascia lata. Its anterior margin is continuous with Poupart's ligament. 



The triangular ligament of the abdomen is a band of tendinous fibres of a 

 triangular shape, which is attached by its apex to the pectineal line, where it is 

 continuous with Gimbernat's ligament. It passes inward beneath the spermatic 

 cord, and expands into a somewhat fan-shaped fascia, lying behind the inner pillar 

 of the external abdominal ring, and in front of the conjoined tendon, and interlaces 

 with the ligament of the other side at the linea alba. 



Dissection. Detach the External oblique by dividing it across, just in front of its attach- 

 ment to the ribs, as far as its posterior border, and separate it below from the crest of the ilium 

 as far as the anterior superior spine ; then separate the muscle carefully from the Internal oblique, 

 which lies beneath, and turn it toward the opposite side. 



The Internal or Ascending oblique muscle (Fig. 29), thinner and smaller 

 than the preceding, beneath which it lies, is of an irregularly quadrilateral form, 



Conjoined tendon. 

 CREMASTER. 



FIG. 293. The internal oblique muscle. 



and situated at the side and fore part of the abdomen. It arises, by fleshy fibres, 

 from the outer half of Poupart's ligament, being attached to the groove on its 



