624 THE VEINS. 



anterior face of the tarsal articulations by means of several anastomosing 

 roots, the principal of which is formed by the deep metatar'sal vein, that 

 passes through the cuboido-cuneo-scaphoid canal from behind to before. 

 After crossing the fibular arch with the artery, it joins the posterior tibial 

 to constitute the popliteal vein. 



B. POSTERIOR TIBIAL VEIN. This commences near the hollow of the 

 hock, within the calcis, by radicular branches which principally come from 

 the two saphena veins. It then ascends along its satellite art-ery, to open 

 into the anterior vein beneath the popliteal muscle. 



6. Superficial Veins of the Leg. 

 These are the internal and external saphena. 



A. INTERNAL SAPHENA VEIN. This vessel shows two roots an anterior 

 and posterior (Fig. 293, 39, 40). 



The first proceeds from the internal metatarsal vein, the second from the 

 external. Both ascend, in converging towards each other, on the internal 

 face of the tibia, uniting into a single branch before reaching the thigh. 



This single branch, always very voluminous, glides upwards on the 

 sartorius muscle, and terminates in a variable manner on reaching the groin : 

 sometimes it is insinuated into the interstice of the two adductors of the 

 leg, to join the femoral vein, and at other times it ascends to the ring of the 

 short adductor, and opens into the external pudic veins. 



B. EXTERNAL SAPHENA VEIN. It rises, by a short branch, outside the 

 os calcis, communicates, even at its origin, with the posterior root of the 

 internal saphena by means of a large reticular anastomosis thrown trans- 

 versely in front of the apex of the calcis ; and with the posterior tibial, by a 

 large branch which passes between the tibia and the perforans muscle. It 

 follows the external saphena nerve outside the gastrocnemii tendons, behind 

 the external gastrocnemius muscle, and enters the popliteal vein, after 

 joining the femoro-popliteal vessel. . 



7. Metatarsal Veins. 



These veins arc three in number, and are distinguished as internal, 

 external, and deep ; they proceed from the sesamoid arch, which is formed 

 by the anastomosis of the two digital veins. 



A. INTERNAL METATARSAL VEIN (Fig. 278, 9). This vessel, the most 

 considerable of the three, appears more particularly to continue the digital 

 vein of the same side. For the greater part ' of its extent it is placed with 

 the internal plantar nerve, along, and a little in advance of, the flexor 

 tendons. Arriving near the tarsus, it deviates slightly to reach the anterior 

 face of the tarsal articulations, and there communicates, by a very large 

 transverse branch, with the origin of the anterior tibial vein ; afterwards it 

 rises on the internal face of the leg, where it constitutes the anterior root of 

 the internal saphena vein. 



B. EXTERNAL METATARSAL VEIN (Fig. 278, 8). It occupies, outside 

 the flexor tendons, a position analogous to the preceding. Towards the 

 superior extremity of the metatarsus, it communicates, by a short thick 

 branch, with the deep vein. It then continues its ascending course by 

 entering the tarsal sheath along with the plantar arteries, and is prolonged 

 in the hollow of the hock, along the great femoro-popliteal nerve, in con- 

 stituting the posterior root of the internal saphena. 



0. DEEP METATARSAL VEIN (Fig. 278, 10). This is placed beneath 



