250 ANATOMY OF THE DOMESTIC FOWL 



nal wall, draining the skin of the inner surface of the upper portion 

 of the thigh, the adductor muscles, and the region of the abdominal 

 and the breast border. It crosses the ischiadic artery in a diagonal 

 direction, and enters the vena cruralis in the middle of the crural 

 region. 



Second, the vena femoralis interna profunda (Fig. 69, No. 3) forms 

 a communication between the end of the suralis near the knee. It 

 lies on the median portion of the flexor cruris internus muscle. 



Third, the vena femoralis anterior (Fig. 69, No. 4) is formed 

 from branches from the sartorius and adjacent structures, and 

 anteriorly empties into the crural vein near where the latter enters 

 the abdominal cavity. 



Fourth, the vena epigastrica (Fig. 70, No. 33) is formed by branches 

 from the abdominal wall and branches from the walls of the abdomi- 

 nal air-sacs. It passes along the median surface of the os pubis 

 and ends into the vena cruralis near the spine of the ilio-pubica or at 

 a point where these join with the vena hypogastrica. 



VEINS OF THE CAUDAL REGION AND OF THE PELVIC CAVITY 



The vena iliaca interna or the vena hypogastrica (Fig. 70, No. 22) 

 collects most of the blood from the tail. The vena iliaca interna 

 collects most of the blood from the pelvic cavity, and the adjacent 

 intestines. It unites with the vena iliaca externa (Fig. 70, No. 27) 

 and receives the vena renalis magna and forms the trunk of the 

 vena iliaca communis (Fig. 70, No. 26). 



The vena coccygea originates between the coccygeal vertebrae, 

 and coUects the blood from the region of the tail, including the tail 

 feathers, the tail muscles, the tail gland, and the skin of the region. 

 These small collecting vessels form a trunk on each side of the coccyx. 

 The right and the left pass laterally, each one taking up a vena 

 cutanea et pudenda, and frequently anastomosing with the vessels 

 on the other side. These often unite into one vessel. Both trunks 

 are connected by a transverse, or anastomotic, vessel. At this 

 anastomosis there empty into it the vena coccygea mesenterica and 

 the vena portalis. There also communicate at this point the right 

 and the left hypogastrica caudalis. In its course it is partly im- 

 bedded in the kidney and passes anteriorly to the vena iliaca com- 

 munis. This circle is called the arcus hypogastricus. Thus the 



