Frank A. Stromsten 477 



parts of the pelvis (especially the external genitals, cloaca, etc.) and 

 pass forward to the ventral surface of the kidneys where they open into 

 the anterior advehent veins in the manner descrihed ahove. They give 

 off afferent veins to the kidneys, testes (or ovaries) with their ducts, and 

 to the suprarenal hodies. In the large snapping turtle {Cliehjdra ser- 

 pentina) they also make direct connections with the roots of the post- 

 cava. Jourdain, 59, denies that such a direct connection takes place. 

 The writer has not been able to trace such connections in Kinosternon, 

 nor, indeed, in all of the snappers. In the smaller turtles these connec- 

 tions could not be made out except by a successful celloidin corrosion 

 €ven if they were present on account of the extreme smallness of the 

 veins. Bojanus, 19, shows such a connection in his figure 12-i, plate 

 XXY, 0*, of Testudo europcece, but this is probably the result of his 

 ■erroneous idea of the real significance of the veins of the kidney. 



The external revehent veins, or the iliacs of Bojanus, arise as dorsal 

 branches of the circumflex iliacs. Each receives, before reaching the 

 kidnev, a large branch from external border of the shell (not shown in 

 figure). This border vein receives the terminal ends of the intercostal 

 veins, and the veins from the fat body. 



According to Nicholai, 26, and later Martino, 41, all three of these 

 veins act as afferents to the kidneys. Jourdain, 59, supposed, however, 

 that this need not always be the case, but that sometimes the blood 

 current of the iliacs may be reversed. At all events, it appears that the 

 hlood from the circumflex iliacs is usually divided so that a part of it 

 must pass through the capillaries of the kidney to the postcava, while 

 another part must pass through the hepatic network before reaching the 

 heart. Therefore, it does not seem improbable that at times a larger 

 amount of blood may pass through the iliacs to the kidneys than at 

 others, and that under certain conditions the blood current in this short 

 vein may actually be reversed. 



The circumflex iliac vein (vena iliaca circumflexa) is formed by the 

 nnion of the ischiadic and the common coccygeal veins. The common 

 •coccygeal vein arises from several veins of the caudal region, the more 

 important of which are : the superior coccygeal, the lateral coccygeal, 

 the lateral cloacal, and the lateral caudal. The latter two veins often 

 unite to form a short single stem just before opening into the common 

 coccygeal. The circumflex iliac divides in front of the pelvis into a 

 dorsal and a ventral branch, the iliac and the abdominal veins, respec- 

 tively. 



The abdominal veins extend along the ventral wall of the body from 

 the pelvis to the liver. They are connected in front of the pelvis by a 



