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Show 480 MR. F. E. BEDDARD ON THE [Nov. 28, have been published by the Society*, attempted to fill in some of the lacunte in our knowledge of an undoubtedly interesting genus of Lacertilia, the systematic position of which within the order cannot certainly at present be regarded as conclusively decided t. Mesenteries and Veins of the Liver.-The hepatic ligaments are quite typically Lacertilian, though presenting apparent differences from those of other Lacertilia, which are due simply to the snakelike form of Amphisbcena and the correspondingly snake-like form of the liver. In my example of Amphisbcena brasiliana, measuring 15 inches in total length, the liver is 107 mm. or nearly 4| inches. The smaller left lobe, which extends neither so far forward nor so far backward as the right lobe i, is only 73 mm. long. It may be noticed in passing that the liver shows several rather obliquely placed transverse fissures, a state of affairs which is known to exist in burrowing, and also in marine, snakes and in the burrowing Cfecilians. The transverse lobation of the liver is not, however, a very marked phenomenon in this Lizard and might easily be, as it has been by some at any rate §, overlooked. The umbilical ligament is, as in other Lizards, attached along the whole length of the liver from beginning to end. It does not, however, end with the liver, but is prolonged further, in fact to the very end of the abdominal cavity. This fact has been noted by Butler ||, whose remarks, in so far as they bear upon the matter under consideration, are as follows " In many Lizards these fat-bodies, pushing the peritoneum before them, bulge into the body-cavity; and, lying on the course of the large vessel, ventral to the . . . . bladder . . . . and the alimentary canal, into the ventral ligament of which they in some forms (Amphisbsenidfe) obviously extend," &c. Posteriorly, however, in the present species the umbilical ligament is not attached to the gut. It leaves the liver for the stomach at the gall-bladder and ceases to be attached to the stomach on a level with the posterior extremity of the right lobe of the liver. The ligament is single throughout. The liver is attached dorsally by membranes which find their homologues in other Lacertilia and are indeed but little altered from the arrangements found generally. There are two of these membranes. The left-hand one attaches the left lobe of the liver to the stomach, and the right-hand membrane is the " Hohlvene-gekrose " of Hochstetter, which attaches the vena cava to the dorsal parietes posteriorly and is continued on to the gonad, and which anteriorly has somewhat varying relations among the Lacertilia to the stomach and the parietes. In Amphisbcena this mesentery does not reach the dorsal body-wall independently * P. Z. S. 1904, 1905. + F01- a resume of opinion, see Fiirbringer, " Beitrag z. Systematik und Genealogie der Reptilien, Jen. Zeitschr. xxxiv. 1900, p. 616. J It thus differs from A. cinerea as figured by v. Bedriaga, Arch. Nature, p 481 1884, pi. iv. fig. 2. § cF ;/' C™ > ( Le?ons d'Anat. Comp.' ed. 2, vol. iv. part ii. (1835). || On the Relations of the Fat-Bodies of the Sauropsida," P. Z. S. 1889, |