1904.] CIRCULATORY SYSTEM IX THE OPHIDIA. 337 



the artery to the anterior testes for the supply of the fat-body, 

 two twigs are given off from the longitudinal vessel just in front 

 of the posterior testes which also supply the fat-body. This blood- 

 supply has been ah^eady referred to in writing of the arteries of 

 the fat-body. 



Arteries of Fat-Body. -^^^.oh. fat-body, which is not particularly 

 well developed, is enclosed in a separate coeloniic space. It reaches 

 from just behind the liver to about the end of the first third of 

 the more anteriorly-situated kidney. The longitudinal artery 

 does not, however, so far as I can ascertain, run through the 

 entire length of the fat-body. The main artery of the fat-body 

 arises from the aorta far back, exactly between the posterior 

 testis and the anterior kidney, just in front and to one side of 

 the posterior rectal artery. It gives ofi' a minute branch, which 

 runs forward and belongs to the system of vessels supplying the 

 vas deferens. It then divides into two equally stout branches, 

 which supply respectively the anterior and the posterior region 

 of the fat-body. The division of the artery takes place some 

 way before it reaches the fat-body itself. The posterior branch 

 ends posteriorly with the fat- body ; the anterior branch extends 

 forwards to the superior mesenteric artery which it joins. 



The longitudinal artery of the fat-body also receives another 

 strong branch from the aorta in front of the posterior mesenteric 

 and between it and the other testis*. A more slender tributary 

 arises from the first of the testicular arteries supplying the 

 anterior testis, and a second from the region of the posterior 

 testis. The fat-body arteiy has thus three main origins and 

 two less impoi-tant ones. 



The longitudinal trunk along its course gives off repeated 

 branches to the lobes of the fat-bodies on both sides and also 

 epigastric branches, the number of which will be referred to 

 under the description of the epigastric system. Anteriorly to the 

 origin of the fat-body artery from the mesenteric artery the fat- 

 body is supplied by a series of branches of the various viscei'al 

 arteries. The longitudinal vein of the fat-body (anterior abdo- 

 minal) closely accompanies the artery ; it finally joins the main 

 portal trunk in the region of the mesenteric artery. 



Intercostal Veins of the Portal Systems. — In the anterior region 

 of the body, in front of the heart, there are a series of intercostal 

 veins which pour their blood directly into the heart through the 

 vertebral and jugular veins. In the thoi'acic and abdominal 

 regions are other intercostal veins, which are connected with the 

 portal system of the liver and of other viscera. The first few, 

 and they are indeed very few, belong to the hepatic portal 

 system. They vary, as do the intercostal arteries, as to the side 

 of the median dorsal line from which they arise. The first six of 

 these vessels arise from the left, the next two from the right side. 

 There are, in fact, only eight of them. The first arises between 



* It is noteworthy that the two chief ai'teries of the fat-hodj^ arise on different 

 sides of the aorta. 



Proc. Zool. Soc— 1904, Yol. I. No. XXII. 22 



