624 MR. c. H. o'donoghue on the 



The following vessels then come off from the dorsal aorta in 

 order : — 



1. The Lieyio-gastric Artery is the first of these. Its gastric 

 branch is the main artery supplying the stomach, and it also sends 

 a branch to the spleen, and yet a third, the cystic artery, to the 

 gall-bladder. No branch of it goes to the pancreas, nor does 

 the superior mesenteric artery send twigs to the spleen and gall- 

 bladder as Beddard (1) has described in Tropidonotios fasciatus. 



2. The Superior Mesenteric Artery is the largest vessel arising 

 from the dorsal aorta. Soon after its origin at about the level 

 of the pancreas it divides into two branches ; a smaller one, the 

 duodenal, running anteriorly supplies the part of the intestine 

 immediately after the pylorus and also the pancreas; a much 

 larger one running posteriorly supplies the manj^ coils of the 

 intestine as far back as the posterior end of the right ovary. 

 Small branches from it also supply the anterior part of the fat- 

 body. I have been unable to find any branch of this artery 

 running to the right ovary such as Beddard (1) recorded in 

 Trojndonotus fasciatus. 



3. The Right Ovarian Artery^ a moderate-sized vessel, runs to 

 the right supra-renal body and, dividing into anterior and pos- 

 terior branches, forms a longitudinal vessel along it. From this 

 longitudinal trunk are given off : — 



(a) Six small ovarian arteries of equal size. 



{b) Three somewhat larger oviducal arteries. One of these 

 arises from the anterior end of the longitudinal vessel 

 and supplies the fimbriated opening of the oviduct, and 

 the other two arise from the posterior end. 



(c) Three fat-body arteries — an anterior, a small median, and 

 a posterior. 



(fZ) A number of fine twigs to the supra-renal body. 



The posterior of the three fat-body arteries in some cases has 

 an independent origin from the aorta. 



4. The First Inferior Mesenteric Artery supplies the coils of the 

 intestine just posterior to the right ovary. Its point of origin 

 varies, however, in different individuals and in the two sexes, as 

 will be pointed out below. 



5. The Anterior Right Renal Artery conveys blood to the 

 anterior half of the right kidney, and also gives off a branch to 

 the right oviduct. 



6. The Left Ovarian Artery is distribiited in a very similar way 

 to the right, and from the longitudinal trunk it forms along the 

 supra-renal body come off : — 



(a) Five equisized ovarian arteries. 



(h) Three oviducal arteries. The anterior again supplies the 

 oviducal funnel. 



(c) Two fat- body arteries. 



[d) A number of fine twigs to the supra-renal body. 



As on the right side the posterior of the fat-body arteries may 

 arise separately from the aorta. 



