DISSECTING MANUAL. 



over the symphysis, skin over Scarpa's triangle above and in- 

 ternally, top of scrotum, and root and dorsum of penis (mons 

 Veneris and labium ma jus). [642] 



Genito-crural. Arising by two roots which unite in the 

 Psoas, the nerve then pierces and descends in front of the Psoas 

 and runs through the psoas fascia and along the outer side of 

 the iliac vessels under the ureter; it divides above Poupart's 

 ligament into two branches, genital and crural. The minute 

 genital branch runs across the iliac vessels and through the in- 

 guinal canal to the skin of the scrotum (or labium majus) and 

 adjacent part of the thigh; branches go to the external iliac 

 artery, Cremaster, and sympathetic spermatic plexus. The 

 crural branch runs on the outer side of the femoral artery and 

 through the saphenous opening, or iliac part of fascia lata, to 

 the skin over Scarpa's triangle external to the ilio-inguinal ; it 

 supplies the femoral artery and communicates with the middle 

 cutaneous. [643] 



External Cutaneous. This runs under the Psoas and across 

 the Iliacus, under the iliac fascia, to the anterior superior iliac 

 spine, and then under the outer end of Poupart's ligament, 

 either over, under, or through the Sartorius origin. Then, after 

 giving off small branches, it pierces the fascia lata four inches 

 below the spine and divides into two branches. The anterior 

 branch, the larger, supplies the outer side of the front of the 

 thigh, almost to the knee. The posterior branch supplies the 

 outer side of the buttock below the great trochanter, and the 

 upper two- thirds of the outer side of the thigh. [643] 



Obturator. Arising by three roots which unite in the Psoas 

 and emerge at its outer border, the nerve descends behind the 

 common iliac and along the outer side of the internal iliac ves- 

 sels. It then runs below the pelvic brim with the obturator 

 artery, and through the obturator groove of the thyroid fora- 

 men, where it divides into two branches, superficial and deep. 

 The deep branch pierces the Obturator externus, descends be- 

 tween the Adductor brevis and magnus, pierces the latter, and 



[280] 



