1904.] CIRCULATORY SY.Sl'EM IX THE OPIIIDIA. 365 



gastric branches gives off two small branches to a couple of small 

 glands which lie at the anterior end of the anteriorly situated 

 testis. These glands resemble in a curious way the posteriorly 

 lying spleen and pancreas, and show the same diffei'ences in colour. 

 Contrary to what is usually found in snakes, and correlated 

 perhaps with the foi-waixl position of the testes, the Jirst spermatic 

 artery arises between the last gastric and the supei-ioi- mesenteric. 

 Arrived at the testis, which it reaches at about the end of the 

 first quarter, the ai'tery divides into an anterior and a posterior 

 longitudinally running branch. The latter gives off shortly a 

 slender and ventrally running branch to the peritoneal sheets 

 envolving the portal vein &c. Further back, and just in front 

 of the supeiior mesenteric, a dorsally running twig supplies what 

 is, I presume, the mesorchium. Immediately after the supei-ior 

 mesenteric arises the second sjiermatic artery of this testis. The 

 third spermatic arises a little farthei' on, close to the end of the 

 testis, and between them arises, from tlie longitudinal testicular 

 artery, a branch to the mesorchium. The third spermatic arteiy 

 gives off before reaching the testis a branch en eithe];" side to 

 the mesorchium. Between ■ the two posterior spermatic arteries 

 the adrenal portal vein lies, passing to the adrenal body from the 

 pa-rietes on the right side of the aorta. 



The left (posterior) testis has only two spermatic arteries, 

 which lie, relatively speaking, in the same position as the second 

 and third spermatic arteries of the right testis. The last of 

 these gives off before reaching the testes a branch to the mes- 

 orchium, which is the only branch of the kind that I could find. 



Posterior testis and blood-supply of Fijtlion spilofes. 

 Lettering as in text-fig. 76. 



On the other hand, the longitudinal testicular artery gives off at 

 least four slender branches, ventral in direction, which supply 

 the fat-body. The most anterior of these joins a twig of the 

 superior mesenteric which also supplies the fat-body. The 

 superior mesenteric thus also contributes to the blood-supply of 

 the testes. 



