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Show 1905.] VASCULAR SYSTEM OF LACERTILIA. 485 related Opliidia. A likeness between Hatteria and the Ophidia fits in well with the view that Hatteria, though unquestionably an ancient form, is nevertheless to be placed closer to the Squamata than to any other group of Reptiles. The Amphisbfenids undoubtedly differ much from other Lacertilia, not only in structures related to their apodous condition and snake-like habit, but in various features which have at least 110 obvious connection with their mode of life. There are no clear indications of their relationship to other Lacertilia*. It may be that the fact dealt with above is of some suggestiveness as a. clue to the position of this group, which, judging from its distribution and great modification, would not seem to be a modern type of Lacertilian. Other Veins.-It has been recorded by v. Bedriaga that the posterior vena cava of Amphisbcena shows no divergences from the Lacertilian type. The left vena renalis revehens turns abruptly to the right at about the middle of the testis, where it receives the left spermatic vein, and from the right vena renalis revehens where the latter receives the right spermatic vein. In its course the vena renalis revehens of the right side (no doubt of the left also, though I have not positively ascertained the fact) appears to receive several veins from the parietes. These, however, really open into a vein to be described later. Supra-renal portal veins exist. There were two 011 the left side and two on the right. On the right side, where circumstances allowed a more careful study, these veins were seen to open into a vein running along the vas deferens as figured by Hochstetter f for Lacerta viridis. But in Amphisbcena this vein runs back to the kidney and receives in its course between the testis and the kidney four veins from the parietes springing close to the dorsal line. In continuation of this series three veins open into each kidney. This vein is shown in the accompanying figure (text-fig. 68, p. 486). It is clearly the equivalent of the vena deferentialis figured and described by Hochstetter in Varanus J. He does not, however, mention branches to it from the parietes, such as occur in Amphisbcena. Considering this latter fact and the relations of the vein to the vas deferens (Wolffian duct), I imagine that it is to be regarded as a persistent, though small, posterior cardinal vein. V. Bedriaga, in his illustration § of the viscera and vascular canals in Amphisbcena cinerea, shows veins from the parietes opening into the vena renalis revehens of the left side. But this illustration refers to a female example, in which the vein which I have just described may not exist. Moreover, veins running along the oviducal membrane and opening into the kidney-system, such as exist in other Lizards, are obviously not the homologues * They are, as it appears to me, rightly regarded by Fiirbringer as a suborder equivalent to Lacertilia vera, Chamadeouta, &c. t Morph. JB. xix. Taf. xvi. fig. 13. |