444 A MANUAL OF ANATOMY. 



Insertion. By muscular fibres into the anterior half of 

 the external lip of the iliac crest. By its aponeurosis, which 

 unites in the middle line with the opposite muscle (as well 

 as all the other lateral abdominal muscles), to form the 

 linea alba, extending from the ensiform to the symphysis. 

 By a dense band of the aponeurosis, which extends from 

 the anterior superior spine of the ilium over the femoral 

 vessels to the spine, iliopectineal line, crest and front of the 

 pubes. The portion of this band attached to the spine of 

 the pubes is Poupart's ligament, the reflection to the ilio- 

 pectineal line is Gimbernat's ligament. 



The Linea Alba. Fig. 89. Diag. 29. 



This is the fascial junction of all the lateral abdominal 

 muscles in the middle line from the ensiform appendix to 

 the symphysis pubis. 



A gap is left between the fibres of the external oblique 

 over the spine of the pubes, through which passes the sper- 

 matic cord in the male and the round ligament in the 

 female. This is the external abdominal ring- or opening-. 

 Figs. 89 to 93. 



The outer border of the ring is formed by Poupart's liga- 

 ment, the inner, by the fibres of the aponeurosis passing to 

 the front of the pubes ; these borders are called columns. 

 In order to strengthen this weak spot in the abdominal 

 wall these columns are bound together by fibres passing at 

 right angles to them, and extending outward to near the 

 anterior superior iliac spine. These fibres constitute the 

 intercolumnar fascia. From the lower part of the inter- 

 columnar fascia and the margins of the ring a thin membrane 

 descends upon the cord ; this is the external spermatic 

 fascia. It is these structures that close in the gap between 

 the separated fibres of the external oblique and effectually 



