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Show the fully developed left lung (the only lung, as Mr. G.. W. Butler has correctly asserted, which exists in Amphisbcena). P ^ „ hepatic ligament in question is attached to theou ei or ei the lung, where it is first visible (text-fig. 66, B) at some little distance from the commencement of the lung, u a a grea er distance from the termination posteriorly of that viscus. it is seen to be covered by the umbilical ligament when the repti e is dissected so as to leave the umbilical ligament on the lett side; it is furthermore attached at first to that ligament, and has therefore a common attachment with it to the liver. Fuit ei forward (text-fig. 66, C) the course of the attachment of the pulmo-hepatic ligament gradually moves over the lung oblique y until it comes to lie upon its inner border, i. e. that nearest to the liver, or rather by this time the vena cava, for the liver-substance ends anteriorly a good way behind the heart. At the same time the umbilical ligament moves obliquely in the line of its attachment in the opposite direction, so that ultimately (text-fig. 66, A) the inner edge of the lung is tied to the opposite edge of the vena cava by a short mesentery which is formed by the fused pulmo-hepatic and umbilical ligaments, while the inner edge of the lung is attached to the median parietes by a ligament which is presumably umbilical ligament only. These relations will be understood by an inspection of the accompanying figures (text-fig. 66), which represent a series of diagrammatic transverse sections through the region of the liver and lung which are dealt with here. These attachments between the liver and lung are not peculiar to Amphisbcena, as I believe ; but they are specially obvious in that Lizard on account of the elongation of the organs concerned. The only other ligament in this region of the body which remains to be noticed is the pulmo-gastric, which attaches the lving to the stomach. It extends along the whole lung, and is continued beyond it as a fold upon the stomach, extending back as far as the spleen. Amphisbcena agrees with other Lizards in the possession of a parieto-hepatic system of veins, which seem, however, to be limited to the dorsal body-wall. I could at least observe no such veins in the umbilical ligament belonging to the ventral epigastric system. Of the former there are, as Mr. G. W. Butler has correctly pointed out *, five veins distributed along the course of the liver, and not limited, as they so often are, to the right lobe where it is free from the left. These veins (text-fig. 67) are large and for the most part bifurcate with a long course between the point of evergence from the body-wall and of entrance into the liver. They run, of course, in the right hepato-dorsal mesentery. The large number of these veins is not an important character, for in Scincus officinalis I find as many as six. It is their extension along the whole length of the liver which is worthy of note, and is a likeness to the conditions which obtain in the Ophidia. 482 MR. F. E. BEDDARD ON THE [N O V . 28, * P. Z. S. 1895, p. 699, footnote. |