386 MUSCLES. 



Chord in the male, and of the Round Ligament of the Uterus in 

 the female. This opening is named the External Abdominal 

 Ring. The tendon forming its upper boundary is inserted into 

 the symphysis pubis, and into the pubes of the opposite side, by 

 fibres which are interwoven with and decussate those of its fel- 

 low. The tendon forming the lower margin of the ring is in- 

 serted into the spine of the pubes, and into its crislafor an inch. 

 The portion inserted into the crista of the pubes is Gimbernat' s 

 ligament, which it will be readily understood, means only a 

 part of the Crural Arch. 



The Ring in the External Oblique is rather triangular than 

 round; its base is formed by the body of the pubes, and its point 

 is at the place where the tendon splits. The latter is kept from 

 parting still farther by a fasciculus of tendinous fibres, which 

 runs across it The sides of this opening are called its Columns, 

 and from their situation, internal and external, or upper and 

 lower Columns. In the female it is oval and scarcely half an 

 inch long. 



There are several small round holes in the tendon of this 

 muscle, which afford passage to nerves and to veins. When, 

 by the clearness of the dissection, the tendon has its characte- 

 ristic gloss and polish, they are very distinct. 



Use. This muscle compresses the viscera of the abdomen 

 and brings the pelvis and thorax towards each other.* 



The Obliquus Interims, 



Lies beneath the last, and its fibres pass in a contrary direc- 

 tion to the fibres of the other. It arises tendinous, by the fascia 

 lumborum, from the three inferior spinous processes of the loins 

 and from all those of the sacrum; tendinous and fleshy, from the 

 whole length of the crista of the ilium ; and fleshy, from the 

 upper half of Poupart's ligament. Though the fibres of this 



* Varieties. Sometimes a considerable part of its middle and anterior portion 

 is deficient, a vitiated conformation, to which it is subjected along with the other 

 abdominal muscles. The inferior part of its tendon is incompletely developed 

 by the absence of, tbe superficial fibres which retain together the more deeply 

 seated, by which it is weakened and caused to gape by one or more large oblong 

 fissures: this variety gives occasion to a form of inguinal hernia, differing mate- 

 rially from what is common. 



