RESPIRATORY SYSTEMS IN THE OPHIDIA. 



503 



1906.] 



an inequality in the number of renal arteries supplying each, 

 kidney. I find two renal arteries only in the case of the right 

 kidney, and three in the case of the left. 



The vertebi'cd artery also varies in the Ophidia. In the present 



Text-fio-. 88. 



r.c/r. 



Left kidnej'- and adjacent blood-vessels of Ert/throlamprus asculapii. 

 Letterins? as in text-fig. 87. 



species it ceases to run superficially, perforating the musculature 

 about 4 inches behind the snout. The branches of the vertebral 

 are almost segmentally disposed one to each vertebra. Each 



