416 PROCEEDINGS OF THE ACADEMY OF [May, 



After receiving small branches from the muscles of the thigh, the 

 femoral receives near the knee a small branch from the posterior 

 surface of the lower leg, fb, and a larger one, t, that leads from the 

 anterior surface of the lower leg and foot. 



The veins of the pes were so small, in the comparatively small 

 animals it was necessary to use, that their distribution could not 

 be determined with certainty, though they seemed to parallel very 

 closely their corresponding arteries to be described below. 



A short distance caudad to the iliac veins, each epigastric receives 

 one or two fairly large branches from the pelvic region, called by 

 Bronn the ischiadic veins, is. Caudad to the ischiadics and dorsal 

 to the cloaca, each epigastric is united with a short but wide renal 

 portal or renal advehente vein, rp, leading to the posterior border of 

 its respective kidney and receiving, on the way, a short branch 

 from the pelvic region, shown just cephalad to the references lines 

 rt and rp. 



Very close to its junction with the renal portals each epigastric 

 gives off a small branch which unites with its fellow of the opposite 

 side to form a median vein, rt, the rectal leading from the posterior 

 part of the large intestine. A very short distance caudal to these 

 last veins, in the region just dorsal to the anal opening, the epigas- 

 trics are formed by the division of the caudal vein, cv, which, of 

 course, brings blood from the tail and is, on account of the large size 

 of that organ, of considerable caliber. 



The Anterior Vence Cavce and their Branches. 



The entrance of the precaval veins into the heart was mentioned 

 above; their branches, in order from the heart cephalad, will now 

 be described. Since the two precavse are alike, it will be necessary 

 to describe the branches of only one side of the body. After leaving 

 the heart, the precava may be traced forward, for a short distance, 

 at the side of the trachea and cjesophagus, as a wide, thin-walled 

 trunk, fig. 2, vca. The first tributaries that it receives arc the 

 internal mammary and vertebral veins, which join it at the base of 

 the neck at almost the same place. 



The internal mammary, fig. 2, im, is a rather small vein, l)ringing 

 blood from the ventral wall of the thorax. It may be followed 

 along the inner surface of the ribs, near the sternum, in company 

 with its corresponding artery. 



The vertebral vein, fig. 2, v, is also of small diameter and extends 

 to the dorsal body wall near the spinal colunm, from which region 



