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Show 472 MR. F. E. BEDDARD ON THE [Nov. 28, noticed that all three of the important gastro-intestinal arteries in this Lizard arise from the aorta at the same plane exactly. One is not more to the right or left of the median v enti al line or the aorta than the others. The hepatic artery accompanies the conjoined abdominal and portal veins in entering the liver. That organ is also supplied by several small branches (see text-fig. 64, p. 475), which naturally owe their blood to the anterior gastric arteries already mentioned, inasmuch as they accompany the gastric veins, which, as is stated below, pour their contents into the anterior region of the liver. I did not detect any further arterial blood-supply of the liver than from the two sources referred to. Renal Arteries.-These arteries (text-fig. 63, p. 473) are very numerous and show a great regularity, not only in their mode of origin, but in their segmental relations. I counted six separate renal arteries on the right side and seven on the left; and in addition to these the iliac trunks, which also give off the epigastric arteries, send a branch to the kidneys posteriorly. The renal arteries are accurately paired, save that one artery is missing on the right side. That they are otherwise accurately paired is connected with the fact that they all arise in common with the intercostal arteries. Each artery runs over the kidney for some distance before opening into it rather laterally and of course dorsally. Anterior Abdominal Vein.-This vein is typically Lacertilian in origin and distribution. There are nevertheless two or three facts concerning its branches to which it will be necessary to call attention. The vein arises as usual by two roots from the caudal vein. On each side before they unite into the single vein each half gives off two small veins side by side to the posterior part of the kidney posterior in position to the parieto-renal afferent veins mentioned below. After the origin of these a larger vein is given off which runs along the body-wall dorso-ventrally and on the outer side of the kidney. This vein dies away anteriorly before the anterior end of the kidney. It is, as I think, the lateral abdominal vein of other Lacertilia. The anterior abdominal vein runs along the mid-ventral line of the body and is supported by a fold of peritoneum, the continuation backwards of the falciform ligament, and thus the equivalent of the primitive ventral mesentery. The vein joins the portal before entering the liver close to the gallbladder. Hepatic Portal System.---The intestinal portal vein posteriorly frees itself from the large intestine, along which it runs in close apposition, at the junction of the small and large intestines. Henceforth it lies at some distance from the intestine in the mesentery. It is noteworthy that this main portal trunk lies on the left side of the dorsal mesentery, so that it lies superficially to the arteries when this mesentery is viewed from the left side. The vein, moreover, contrasts with the arteries over which it runs |