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Show 2 6 0 MR. F. E. BEDDARD ON THE ANATOMY [ J u n e 6 , umbilical ligaments ancl blood-vessels, it is noteworthy that in Eumeces algeriensis two hepatic arteries are associated each with one of the two umbilical ligaments of that lizard. Gastrosplenic Omentum.-This mesentery is very conspicuous in Gerrhosaurus. It stands out as a free fold with the following r e la t io n s I t arises from the stomach close to the pylorus and passes obliquely downwards supporting the posterior extremity of the spleen, the rest of which lies upon the mesogastrium; it is finally attached to the median dorsal line of the body-wall on a level with the left ovary. This arrangement is practically repeated in Macroscincus, where, however, owing to the position of the viscera, the omentum is shorter, but very strong and fibrous. Moreover the spleen does not even reach, let alone hang over, the edge, as is the case with Gerrhosaurus. In Eumeces, however, the gastrosplenic omentum is identical in its relations with that of Gerrhosaurus, save that it is a little less pronounced as a free fold. I am not describing here a state of affairs which is merely Lacertilian; for in Tupi-nambis the course and relations of the apparently homologous fold are different and do not involve the spleen. Hepato-pulmonary Ligaments.-Gerrhosaurus agrees with the majority of Lizards in that the right lung is suspended by two mesenteries, viz., the hepato-pulmonaiy and dorsal pulmonary. It is noteworthy that the latter mesentery in the case of both lungs extends to the very tip of the organ ; whereas in Eumeces the mesenteries in question do not reach the extremity of the lungs. This is not, however, a characteristic of the Skinks as opposed to Gerrhosaurus, for in Tiliqua the membrane is coextensive with each lung as in Gerrhosaurus. Mr. Butler * observes that " certain Scincoid lizards are as to the relations of their right lungs and liver intermediate between the Teiidse and other Lizards." My own knowledge of the family Scincidse enables me to confirm Mr. Butler; but his accurate statement requires expansion f . In Eumeces, Macroscincus, and Tiliqua there is, in fact, attached to the right lung a pulmo-hepatic ligament which is not so extensive as in, e. g., Gerrhosaurus. In Macroscincus cocteaui this membrane extends rather more than halfway down the lung and ends off upon the dorsal pulmonary ligament, necessarily running in this region in a. direction nearly at right angles to the longitudinal axis of the lung. Whereas in Gerrhosaurus fiavigularis the two pulmonary membranes join behind the right lung ±, in both specimens which I examined. The fact that there is no ligamentous interval between the * " On tlie Subdivision of the Body-cavity in Snakes," P. Z. S. 1892, p. 481. t And has also been expanded by Hochstetter quoted below. J Hochstetter (Morph. Jahrb. xxvii. p. 292) figures the same membranes in some other Skinks, where they appear to agree with those of the forms studied by myself. He says, however, of Gerrhosaurus madagascariensis that the " caudal end of the right lung commences to be isolated from the ligamentum liepato-cavo-pulmonale." It is not so in G. fiavigularis. |