198 HANDBOOK OF ANATOMY 



tack of the thigh and over the calf of the leg. It is a purely 

 cutaneous nerve. 



Branches. Perineal arises at the lower border of gluteus 

 maximus, and, passing inwards, supplies the skin over the peri- 

 neum and external genital organs. 



Gluteal arise beneath gluteus maximus, and, passing round its 

 lower border, supply the skin over the lower half of the 

 buttock. 



Femoral in two sets internal and external supply the skin 

 on the back of the thigh. 



Sural. Two or more branches which pierce the fascia over 

 the popliteal space and supply the skin over the calf of the leg 

 for a variable distance. 



The Great Sciatic nerve passes through the sacro-sciatic 

 foramen below pyriformis between it and the superior gemellus. 

 Covered by gluteus maximus, it passes down, into the thigh, 

 accompanied by the sciatic artery and a special artery of its own 

 (arteria comes nervi ischiadici) . It lies in the hollow between 

 the great trochanter and the tuberosity of the ischium, and enters 

 the thigh beneath the lower border of gluteus maximus. Lying 

 between it and the origin of the hamstrings, it is comparatively 

 superficial. In the thigh it lies on adductor magnus, and is 

 covered by the hamstrings, and at a variable point between 

 the sacro-sciatic foramen and the upper part of the pop- 

 liteal space divides into the internal and external popliteal 

 nerves. 



Branches. Muscular to the hamstrings and short head of 

 biceps. 



Articular to the knee-joint. 



The External Popliteal Nerve. One of the terminal branches 

 of the great sciatic nerve passes beneath the tendon of biceps 

 obliquely through the upper and outer part of the popliteal 

 space ; it then passes over the outer head of gastrocnemius, and 

 just below the head of the fibula divides into its terminal 

 branches, the anterior tibial and musculo-cutaneous nerves. 



Branches. Cutaneous to the skin over the calf of the leg. 

 Peroneal communicating joins a similar bra'nch from the tibial 

 nerve to form the short saphenous nerve. 



