470 



EXTERNAL CUTANEOUS NERVE. 



Fig. 150." 



(ilio- inguinal) also arises from the first 

 lumbar nerve. It is much smaller than 

 the preceding, crosses the quadratus 

 lumborum below it, and curves along 

 the crest of the ilium to the anterior 

 superior spinous process, resting in its 

 course upon the iliac fascia. It there 

 pierces the transversalis fascia and 

 muscle, communicates with the scrotal 

 branch of the ilio-scrotal nerve, and 

 passes along the spermatic canal with 

 the spermatic cord to be similarly dis- 

 tributed. 



The EXTERNAL CUTANEOUS NERVE 

 (inguino-cutaneous) proceeds from the 

 second lumbar nerve. It pierces the 

 posterior fibres of the psoas muscle ; 

 and crossing the iliacus obliquely, lying 

 upon the iliac fascia, to the anterior su- 

 perior spinous process of the ilium, 

 passes into the thigh beneath Poupart's 



* A diagram shewing the lumbar and 

 sacral plexuses, with the nerves of the 

 lower extremity. 1. The five lumbar 

 nerves ; which with a branch from the 

 last dorsal, constitute the lumbar plexus. 

 2. The four upper sacral nerves ; which, 

 with the last lumbar, form the sacral plex- 

 us. 3. The two musculo-cutaneous nerves, 

 branches of the first lumbar nerve. 4. The 

 external cutaneous nerve. 5. The genito- 

 crural nerve. 6. The crural or femoral 

 nerve. 7. Its muscular branches. 8. Its 

 cutaneous branches, middle cutaneous. 9- 

 Its descending or saphenous branches. 10- 

 The short saphenous nerve. 11. The long 

 or internal saphenous. 12. The obturator 

 nerve. 13. The gluteal nerve ; a branch of 

 the lumbo-sacral nerve. 14. The internal 

 pudic nerve 15. The lesser ischiatic 

 nerve. 16. The greater ischiatic nerve. 

 17. The popliteal nerve. 18. The pero- 

 neal nerve. 1Q. The muscular branches of 

 the popliteal. 20. The posterior tibial 

 nerve; dividing at 21, into the two plan- 

 tar nerves. 22. The external saphenous 

 nerve, formed by the union of the com- 

 municans poplitei and communicans pero- 

 nei. 23. The anterior tibial nerve. 24. 

 The musculo-cutaneous nerve, piercing the 

 deep fascia, and dividing into two cutane- 

 ous branches, for the supply of the dorsum 

 of the foot. 



