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Show 614 MR. F. E. BEDDARD ON THE [May 29, upon which I report here, the lateral parietal vein was defective here and there between its origin with the azygos stem from the right superior vena cava and the origin from it of the anterior hepatic branch. After this point it was present as a continuous vessel to some way beyond the origin from it of the suprarenal portal stem. On the left side of the body, the vein originates from the left anterior vena cava at a point nearer to the head than does the right. Thence it is traceable as a continuous vessel to a point just short of the origin from the parietes of the left suprarenal portal. Neither in this individual nor in those previously described by me * is there any connection with the pelvic veins. In other respects there is a fairly close agreement between all three specimens. In Varanus exanthematicus I found rather different features in the azygos and lateral parietal veins. Both anterior venae cavse gave off a backwardly running vein. This vein on the right side arose in front of the subclavian and had a very short course upon the parietes. The vein of the left side arose behind the orifice of the subclavian vein and divided into two short branches. Neither of these veins was connected with the posteriorly situated lateral parietal veins. Posteriorly these veins were obvious on both sides of the body. On the right side they could be traced from opposite the testis into direct communication with the root of the anterior abdominal vein. In this connection therefore with the pelvic veins, the lateral parietal vein of Varanus exanthematicus appears to differ from that of Varanus griseus. On the left side, the connection with the left root of the anterior abdominal vein was also quite obvious, but there was a slight gap along the course of the vein. The connection of the lateral parietal veins with those of the hind limbs obviously brings Varanus more into line with other Lacertilia, where these veins are general and where such a connection occurs. Remains o f Posterior Cardinals.-Hochstetter has mentioned in the case of Varanus griseus a vein which runs along the vas deferens and which he termed the vena deferentialis, describing at the same time its connection with the suprarenal portal veins. The commencement of this vein from the afferent is also figured by him. I have elsewhere t compared this vein to a similar vein in the Boidae and suggested its equivalence to the posterior cardinal. This view was obviously uncertain as long as the conditions obtaining in the female Varanus were unknown. For a vein supplying the vas deferens might be merely regarded as the necessary physiological equivalent of a vein supplying the oviduct and developed ad hoc, without any morphological meaning at all. The same vein, however, exists in the female. I found in a female V. niloticus that the afferent renal vein was prolonged headward of the kidney and ran alongside of the efferent renal vein over the suprarenal body, receiving the suprarenal portal vein, which will be described * Loc. cit. (on p. 610). |