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Show 16 MR. P. E. BEDDARD ON THE [May 3, The azygos veins are to be found on both sides of the bod y; but that of the right side is much the larger, and extends back, for the space of about eight ribs, some little way beyond the anterior end of the lungs. On the left side there is a very slender azygos, which might readily be missed on account of its delicacy. This latter receives, before entering the left jugular, a branch from the oesophagus. In Chamceleon, as I have already pointed out, the oesophageal vein enters the right side of the heart via the azygos vein. Lateral Abdominal Veins.-These veins arise at the junction of each root of the anterior abdominal with the vena renalis advehens. They do not arise from the anterior abdominals themselves as is the case with most Lizards. Their course along the body-wall is, however, like that of many other Lizards. On the right side the vein is connected superficially by slender branches with the dorsal parieto-hepatic veins of that side. Anteriorly the veins die away. Hepatic Portal System.- An in most, but not all, Lizards, nearly the full complement of hepatic portal vessels is present in Pygopus. It receives blood, that is to say, from the anterior abdominal, from the epigastric, the stomach, and the dorsal parietes. There are only wanting independent vessels from the ventral parietes present in many Lizards and so marked a feature of Chamceleon. The epigastric vein appears to be single; if lateral epigastrics are present they are small-unless, indeed, the vessels which I homologise with the lateral abdominals of other Lacertilia are really to be looked upon as lateral epigastrics. The single epigastric lies to the left of the middle line. It is connected with the anterior abdominal by two branches just behind the liver. It gives off a large number of branches to the liver. I counted eight of these altogether: they extend along the whole of the liver, but do not arise at regular intervals, and are of unequal size. Anterior to the liver is a tract of the epigastric which gives off, at any rate, one branch to the vena cava before passing headwards and ending in a way that I have not been able to ascertain. It is noteworthy that here, as in Phelsumco, in both of which there are no marked lateral epigastrics, the median epigastric takes up a portion of the duties of the lateral epigastrics, and conveys some of the blood from the posterior abdominal region straight to the heart. The dorsal parieto-hepatic vessels in this lizard are numerous and large. Altogether three of them enter the liver, and at least two of them are connected, as already mentioned, with the lateral abdominal veins by fine branches running superficially over the parietes. There are also three on the left side, more anteriorly, which communicate with the liver via the stomach. There are four gastrohepatic vessels, which arise separately from a continuous longitudinal trunk running along the stomach, which is fed not only from the vessels of the stomach itself, but also by |