SURGICAL ANATOMY. 379 



clavicle; branches of ' the intercostal nerves; ten or twelve lym- 

 phatic glands, and a quantity of loose adipose and areolar tissue. 



Popliteal Space. 



The popliteal space is a lozenge-shaped space situated at 

 the back of the knee, and forms the ham. It is bounded 



Externally, above the joint, by f the biceps; below the joint, 

 by outer head of gastrocnemius and plantaris; internally, above 

 the joint, semitendinosis, semimembrahosis, gracilis, and sar- 

 torius; below the joint, by inner head of the gastrocnemius. 



It is cover cf/ in by the skin, superficial fascia, and fascia lata. 



Its floor is formed by the lower part of the posterior surface 

 of the femur, the liga mention posticurn Winslowi, and the pop- 

 liteus muscle and its fascia. 



It con In in*: 



The popliteal artery and branches; popliteal vein receiving 

 the external saphenous vein (vein to the outer side) ; internal 

 and external popliteal nerves and branches ; articular branch of 

 obturator nerve; branch of small sciatic nerve; four or six 

 lymphatic glands, and a quantity of adipose and areolar tissue. 



ANATOMY OF HERNIA. 



Hernia is the protrusion x of any part of a viscus from its 



natural cavity through the enclosing walls of the cavity. As 

 usually understood, it refers to the protrusion of the intestine or 

 mesentery, or both, from the abdominal cavity. The most com- 

 mon forms are : 



Kxternal or oblique inguinal hernia; 

 Internal or direct inguinal hernia; 

 Femoral hernia; 

 Umbilical hernia. 



1. Ol'.uoj'i- [NGUINAL MKUN1A escapes from abdominal cav- 

 ity at the internal abdominal ring, carrying before it a pouch 

 of peritoneum, descends along the inguinal canal in front of the 

 cord, and emerges at the external opening. The anatomical 

 parts concerned are the inguinal canal, with its internal and 

 external abdominal rings, the transversalis fascia (vide Fascia), 

 the peritoneum (ride Peritoneum ). and Pouparfs ligament. 



The inguinal or x/yrn/m//V nunil is about one and a half 

 inches in length, extending from the internal abdominal ring 

 to the external abdominal ring. It serves lor the passage of the 



