414 SPECIAL ANATOMY. 



crista ilei, and terminates in the skin over the abdominal ring and 

 mons Veneris, or passes through the inguinal canal. It supplies 

 the above-mentioned muscles. 



2. N. ileo-inguinalis arises from the first lumbar nerve or the 

 first loop, perforates m. psoas farther forwards, and the m. trans- 

 versus in the neighbourhood of spina ilei anterior super., after 

 that the obliq. intern., and passes over the spermatic cord (or the 

 round ligament), through the abdominal ring to the skin of the 

 pubic region (mons Veneris) and the anterior external part of the 

 scrotum (or the labia externa), sometimes even to the thigh. 



3. N. genito-cruralis arises from the second lumbar nerve, or 

 the second loop, perforates the psoas close in front, passes down- 

 wards, forwards and outwards upon its anterior surface, and 

 divides in the inguinal region into an internal and external 

 branch. 



a. Ram. externus s. lumbo-inguinalis, passes off obliquely, 

 from the psoas to the m. iliacus outwards, and passes upon 

 this with an external branch to the spina anter. super., per- 

 forates the inferior border of the abdominal muscles, and 

 supplies the skin of the outer superior part of the thigh ; 

 with an internal, upon or outside the art. cruralis, through 

 the femoral ring to the skin of the anterior superior part of 

 the thigh. 



b. Ram. internus s. n. spermaticus externus [s. ileo-inguinal] 

 runs through the femoral ring on the inner side of v. cruralis, 

 with an external branch which terminates in the inguinal 

 glands over Poupart's ligament and the skin ; with an inter- 

 nal branch through the inguinal canal upon the spermatic 

 cord (or lig. uteri rotund.) into the tunica vaginalis propria 

 to m. cremaster, testicle, tunica dartos, and skin of the scro- 

 tum (or to mons Veneris and the anterior extremities of the 

 labia). 



665. b. The principal branches, femoral. 



4. N. cutaneus femoris anterior externus [s. inguino-cutaneus], 

 arises from the second loop, perforates the psoas, passes down upon 

 m. iliacus underneath its aponeurosis ; behind art. circumflexa 

 ilei at the outer extremity of lig. Poupartii through a short sheath, 

 here perforates the fascia cruralis, and descends on the outer side 

 of the thigh as far as the knee. Connexions : with the two rami 

 of the genito-cruralis (plexiform). Branches : to the skin over 

 trochanter major, and internally in front. 



5. N. cruralis, the middle and largest branch of the lumbar 



