Frank A. Strom sten . 475 



causes an apparent shifting laterad of the left hepatic vein so that this 

 vein final!}' comes to open into the extreme left end of this organ as in 

 Fig. 1. Some of the small vessels which formerly opened into the left 

 hepatic vein would now open into the sinus venosus, and the number 

 of these would be related to the extent of the backward prolongation of 

 the latter. 



The two veins earlier described as the postabdominals become more 

 important as the hinder limbs increase in size. With the degeneration 

 of the allantois they become the chief tributaries of the intra-embryonic 

 umbilicals and with the latter form the abdominal veins of the adult. 



The abdominal veins are formed from three anlages: (1) the hepatic 

 portion is the remains of the last channels formed by the umbilical veins 

 through the liver to the mesenteric portal, or its tributaries; (2) the 

 portion between the liver and the umbilicus is the remains of the original 

 umbilicals which have been carried mediad by the ingrowth of the con- 

 nective tissue to form the pericardium; and (3) the postabdominals 

 which connect with the iliacs as in the adult. 



RENAL PORTAL SYSTEM. 

 VEIXS OF THE ADULT. 



Fig. 10 is a schematic diagram of the larger body veins of Kinosternon 

 pennsylvanicum . 



The afferent veins of the renal portal system of turtles are the anterior 

 renal advehent, the posterior renal advehent, or hypogastric, and the 

 external renal advehent, or iliac veins. The efferent veins from the 

 kidneys, testes (or ovaries) with their ducts, and veins from the supra- 

 renal bodies open into the two root branches of the postcava. 



The anterior renal advehent vein is a large ventral branch of the 

 posterior vertebral vein of its side. It comes out between the fifth and 

 sixth ribs and passes over the ventral surface of the kidney to open into 

 the posterior renal advehent vein by an end to end anastomosis. In its 

 course it receives an intercostal vein, and gives off numerous branches to 

 the kidney, testis (or ovary), and suprarenal body. The posterior ver- 

 tebral veins which supply the blood to the anterior advehents may be 

 briefly considered at this point. This pair of vessels runs the entire 

 length of the body on each side of the spinal column dorsal to the ribs. 

 They receive the first four intercostal veins and veins from the spinal 

 cord which pass out between the vertebra along with the spinal nerves. 

 Just craniad of the first thoracic vertebra they unite to form a short 

 stem which runs forward a short distance dorsal to the vertebral column, 



