DISSECTION OF THE POSTERIOR LIMB. i 1 



joint and the common insertion of the iliacus and psoas magnus intact 

 for examination by the disse8tor of the abdomen and pelvis. The limb 

 having been removed, it should be placed on a table, and the cut 

 muscles connected with it may be completely cut away after they 

 have been identified. In doing this, a better opportunity will be 

 afforded to observe accurately the insertion of each muscle. Jn remov- 

 ing the lower portion of the biceps, particular care must be taken not 

 to cut the external popliteal and external saphenous nerves, which 

 are included between it and the outer head of the gastrocnemius 

 (Plate 18). 



THE LEG. 



Surface-marking. — The bones of the leg are clothed by muscles 

 except at the inner side of the limb, where the tibia is subcutaneous. 

 This unprotected area of bone corresponds to the shin in man. The 

 superficial muscles of the region {see Plates 17 and 18) form pro- 

 minences more or less distinct, especially in the neighbourhood of 

 the hock, where the various tendons stand out distinctly during the 

 movements of the living animal. 



Position. — In the further dissection of the limb, it may be placed 

 on a clean table, and laid on either side as may be convenient; or 

 a cord may be passed round the femur, and the limb suspended at 

 such a height as just to permit the hoof to come into contact with 

 the table. This latter method has the advantage of keeping the 

 part clean; and, while dissection is being carried on, the leg may 

 be steadied in any position by an assistant. 



Directions. — An incision through the skin is to be carried down the 

 middle line of the limb on its inner side, and terminated a few inches 

 below the hock, where a circular incision may be carried round the 

 limb. The whole of the skin above the circular incision is then to 

 be removed, and the cutaneous nerves and vessels of the region are 

 to be examined. 



The Internal Saphena Vein. On the inner side of the leg, above 

 the hock, two venous branches will be seen to converge and unite to 

 form the internal saphena vein, which is continued up the leg to the 

 thigh, where it has already been dissected. The vessels by whose union 

 the main vein is formed are the upward continuations of the internal 

 and external metatarsal veins. Slender branches of the saphena artery 

 accompany these veins. 



The External Saphena Vein. This vessel begins at the hock, where 

 it communicates with the internal saphena vein, and with the posterior 

 tibial vein. It ascends at the outer side of the gastrocnemius tendon, 

 and, passing between that muscle and the biceps, it empties itself into 

 the femoro-popliteal vein. 



