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Show 440 MR. F. E. BEDDARD OX THE [Mar. 15, gastric before entering the portal vein. The remaining veins are similar in the two specimens. The first to join the main trunk of the portal is a vein from the small intestine ; then follows a much larger trunk, which first of all receives a branch from the small intestine and then divides into two-one splenic and the other gastric. The main trunk is continued along the large intestine, receiving blood from the latter and from the caecum. It will be noticed, therefore, that the portal system of the alimentary canal in Iguana differs in several points from that of Tiliqua, notably in the difference between the branches from the stomach and from the small intestine. A last point in the portal system of this Lizard to which I desire to call attention is a direct connection between the portal system and the systemic veins. A minute vein, which would certainly escape attention in a specimen that had not been injected, arises from the portal vein just at the caecum, and passes along the mesentery to join the branch of the inferior vena cava which supplies the left ovary. Ventral Hepato-parietal veins.-These veins are either two or three in number. The last of them, i. e. that entering the liver nearest to its posterior end, receives a vessel from the anterior abdominal vein, to which reference has already been made (on p. 438). It emerges from the body-wall in the middle line. The middle vessel is formed by the junction of at least three branches-two of these run anteriorly and posteriorly respectively in the middle line, and the former receives a branch from the right side. The most anterior of the three ventral hepato-parietal veins arises from the left side of the ventral median line. Where there are only two ventral hepato-parietal veins, it appeared to me that the anterior of the two represented the two anterior veins of the first specimen fused together. In the third specimen which I dissected (which was not injected) the anterior of the three veins has two important branches which I did not observe in the other specimens. One of these joins the epigastric, as has already been described. The second branch runs forwards and downwards and traverses the middle line of the sternum below the skin; it is exactly comparable to a vein already described in Tiliqua, of which the homologue also appears to exist in Varanus. Dorsal Hepato-parietal veins.-There are either one or two of these veins on the right side, which enter the liver close to the entrance of the vena cava. Where there are two the posterior vein, as will be explained, is detached from the suprarenal system. The more usual single vein in one of the two individuals arises from the parietes and passes along two vertebrae before entering the liver, from which it receives two intercostal branches which are hidden below the musculature. Corresponding to it on the left side of the vertebral column another vein emerges from the parietes and divides into two branches, which embrace the aorta and become continuous with various branches on the stomach which ultimately join the two gastro-hepatic veins ^already |