FASCLE AND MUSCLES. 



or external (intercolumnar fascia), from the edges of the ex- 

 ternal ring. [432] 



Hesselbach's triangle is bounded below by Poupart's liga- 

 ment, internally by the Rectus, and externally by the deep 

 epigastric artery on the mesial side of the internal ring; the 

 fascia transversalis and conjoint tendon form its floor. The 

 spermatic cord, covered by the External oblique aponeurosis, 

 crosses its base. [434] 



Psoas Magnus. Origin; intervertebral discs above each 

 lumbar vertebra, and adjacent margins of vertebrae from 

 lower border of last thoracic to upper border of last lumbar; 

 four aponeurotic arches passing over sides of bodies of upper 

 four lumbar vertebrae; transverse processes of all lumbar 

 vertebrae. Course ; under Poupart's ligament. Insertion ; apex 

 of lesser trochanter of femur. [362] 



Psoas Parvus (inconstant). Origin; intervertebral disc 

 between last thoracic and first lumbar vertebrae, and their con- 

 tiguous margins. Insertion; ileo-pectineal eminence and cen- 

 tre of ilio-pectineal line, by a narrow tendon. [363] 



Iliacus. Origin; around margin of iliac fossa; (partially) 

 anterior sacro-iliac and ilio-lumbar ligaments. Insertion ; outer 

 side of Psoas tendon; anterior surface of small trochanter of 

 femur; (most external fibres) capsule of hip joint. The latter 

 are often separate (Tliacus minor or Ilio-capsularis) . [363] 



The iliac fascia covers the Iliacus and Psoas. [1044] 



Quadratus Lumborum (lying external to the Psoas and be- 

 tween the anterior and middle layers of lumbar aponeurosis) . 

 Origin; posterior part of iliac crest; ilio-lumbar ligament; 

 lower lumbar transverse processes. Insertion; lower border of 

 last rib; upper lumbar transverse processes. [434] 



Fasciae and Muscles of Back. 



Fascia. The superficial fascia is as elsewhere. The deep 

 fascia forms the vertebral aponeurosis, a stronger layer which 

 extends outward from the vertebral spines and over the pos- 

 13 [ 193 ] 



