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Show 476 MR. F. E. BEDDARD ON THE [Nov. 28, with a second epigastric vein, which, running parallel to and above the anterior abdominal, enters the shelter of the liver at its end close to the anterior abdominal and joins that vein under the lower surface of the right lobe before it loses itself in the substance of the liver. The disposition of these veins will be obvious from an inspection of text-fig. 64. Rencd Portal Veins.-In addition to the veins from the tail which bring blood to the kidneys, these glands are also supplied with blood from tlie parietes in their immediate neighbourhood. A series of vessels (see text-fig. 65) arises from the body-walls and plunges into the substance of the kidney on either side. These vessels were for the most part partly injected in the specimen at my disposal and can therefore be accurately mapped. The peritoneum in this region of the body as elsewhere is densely pigmented. But the difficulty of seeing through it is removed by the fact that it is very loosely attached to the parietes and to the kidneys, which lie, of course, behind it. When it is carefully removed the veins in question are very plainly exposed. They arise from the parietes very laterally-that is, not at all close to the median dorsal line, whence such vessels ordinarily arise in Lizards. Originally they appear to have been accurately segmental, one arising from each segment as denoted by a rib. In point of fact, however, the vessels belonging to two or to three ribs occasionally unite before opening into the kidney. It is also to be noted that the veins in question pour their contents into the kidney at different levels. Some vessels enter the kidney along its outer edge, while others plunge into its substance more dorsally. This arrangement is roughly alternate. There were six of these vessels to each kidney, but their distribution was not exactly the same on both sides of the body. These vessels do not appear to be referred to by Hoch-stetter, though he mentions them in Anguis fragiUs. I have noticed them in other Lizards, where possibly they are represented by the veins from the hind limbs. In any case they are very conspicuous and impossible to miss in Ophisaurus, and their arrangement is somewhat different from that which characterises Anguis. It is furthermore to be noted that those veins which enter the kidney more dorsally join in each case one of another series of afferent renals. I counted three of these on the light side, which emerge from the parietes very close to the dorsal middle line. They are rather stouter vessels, and run over the dorsal surface of the kidney nearly to the outer edge of that gland before plunging into its substance. All these parieto-renal vessels become lost in the substance of the kidney. There is no superficially running trunk continuous with the caudal vein posteriorly into which they open. Nor can they be traced into direct and superficial connection with the efferent renal veins. Supra-renal Portal Veins.-These important veins are naturally referred to by Hochstetter, who has done so much towards the elucidation of this as of other venous systems in the Lacertilia. I |