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Show 616 MR. F. E. BEDDARD ON TIIE [May 29, Some originate from the more lateral parietes, either actually from the lateral parietal vein when that is present in this region of the body, or from the area usually occupied by it. Others arise from the parietes near to the dorsal line, and are therefore connected with the posterior vertebral vein. In Varanus niloticus (text-fig. 104, p. 615) I found on the right side two suprarenal portal veins. The anterior of the two was formed by the union of three vessels springing from the lateral parietes. A small vein from the " omentum " joined this vessel. The posterior of the two suprarenals arose from the parietes close to the dorsal line. Both opened into the posterior cardinal vein where it traversed the suprarenal body. On the left side of the body, the anterior of three suprarenal portals arose from the body-wall close to the dorsal line, and thus corresponds exactly to the dorsal parieto-hepatic vein opposite to it. In a specimen of Varanus exanthematicus the arrangement of these portal veins was a little different and is represented in text-fig. 104. The lateral parietal vessel, after leaving the root of the anterior abdominal on the right side of the body, ends in the suprarenal portal in the way illustrated in the figure referred to. The vein thus emerging from the lateral parietal arches over the suprarenal body and divides into two branches, one anterior and one posterior. Each of these again divides into two to supply the suprarenal body, and is also connected with the posterior cardinal vein. A second suprarenal portal arises in front of that just described by a number of branches from the body-wall and joins the continuously running cardinal vein. It also receives a branch arising by many twigs from the " omentum " in the liver region. A third suprarenal portal is anterior to this again and enters the front of the suprarenal gland. On the left side of the body the arrangement was, save for minute details, the same as that which has been described upon the right side of the body. The fewness of the suprarenal portals is thus a characteristic of Varanus as contrasted, for example, with Iguana*. Dorsal Parieto-hepatic Vein.-In the cha pter entitled " Systematis venosi fragmenta " f Oorti speaks of " Vena intervertebralis quae a posteriori pulmonis dextri extremitate obtecta, atque a foramine quodam intervertebrali scaturiens, se in accessorio hepatis lobulo prope venam renalem communem abdit." The vein is figured by Corti, and is also described by Hochstetter* in the same species of Varanus. I have already confirmed the statement of the two anatomists for Varanus griseus §, and I find now precisely the same arrangement in another example of the same species, of which this single vein is doubtless characteristic. It may be observed that in this species, as well as in V. exanthematicus and V. niloticus, V. bengalensis, and V. ocellatus, the vein in question is * P. Z. S. 1904, vol. i. p. 443. X Loc. cit. p. 466. f Loc. cit. p. 48. § P. Z. S. 1904, vol. i. p. 448. |