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Show 364 MK. E. E. BEDDARD ON THE [Feb. 16, branch from the posteriorly running branch of the first hepatic artery. This descending branch also exists in some of the other interspaces, particularly in that between the Vlth and Vllth hepato-cesophageal trunks. All the hepato-cesophageal trunks resemble each other in plan, though differing in detail. They all divide near to the liver into a Y-shaped fork, of which one branch runs forward and unites with the posterior branch of the Y in front. The point at which division occurs varies, but it is generally near to the liver. It is much farther away from the liver in the second branch only, as has been mentioned. Each of these trunks gives off at most three branches, which supply the (esophagus and the walks of the lung. More generally there are only two of these branches, and in the case of the 6th vessel I could find only one. The point at which they are given off varies. Following the eighth vessel, which concludes the series that lie between the oesophagus and the liver, is a ninth branch of the aorta which supplies the same regions. It lies, however, 10 cm. behind the liver and 35 m m . behind the eighth hepato-cesophageal vessel. Between it and the latter are two vertically running branches of itself and the eighth trunk precisely like that which lies between vessels 6 and 7. This ninth vessel is at once the last which supplies the liver and the first which supplies the fat-body. The gastric region of the alimentary tract is supplied by three arteries, of which the third and last is very much the most important. All of these arteries give off a branch or branches to the fat-body. Both of the first two smaller gastric arteries come Text-fig. 76. Anterior testis and blood-supply of Python spilotes. Ao., aorta; F.B., arteries to fat-body; Sr.V., suprarenal portal vein; T, testis ; S.mes., superior mesenteric artery. into direct relations with the third and largest artery. The latter gives off two branches which run forward along the stomach ; each of these ultimately ends in the main twig of gastric arteries 1 and 2. The third gastric artery before it divides into these two |