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Show 1903.] ANATOMY OF T H E JAPANESE SALAMANDER. 299 great Amphibian which died in the Society's Gardens enables me, however, to add a few new facts to what is already known of its structure. The larger example measures 39 inches, the smaller 20 inches. The large Megalobatrachus was injected, and though the injection did not run with equal regularity through all the branches of the arterial system, certain regions were filled with the gelatine, and allow of the description of quite minute arteries, some of which are of importance and apparently have not been described. § On certain of the Abdominal Viscera. About one-third of the length of the right lung is free from any mesenteric attachments, and lies freely over the abdominal viscera. The rest of this organ, nearly up to the root, depends by two mesenteries which are inserted along the internal edge of the lung where the pulmonary artery runs. One of these mesenteries attaches the lung to the liver, the other to the aorta posteriorly, and to the oesophagus anteriorly after the origin of the gastric artery. Anteriorly the two mesenteries arise separately from the lung ; posteriorly they arise in common and ultimately become fused into one membrane, which at the end of the liver is continuous with the mesoarium. The tip of the left lung is also free from mesentery, but for a shorter space than that of the right lung. One membrane only is attached to it, which passes to the oesophagus and stomach anteriorly, and posteriorly joins the mesogastrium. Posteriorly the spleen is suspended in the mesogastrium, and between the spleen and the lung is a funnel-shaped depression of the mesentery up which passes the gastro-splenic artery. Posteriorly, the mesentery attaching the stomach to the aorta passes into the mesoarium, as has been described on the right side of the body. The liver is furthermore attached to the oesophagus and stomach by a membrane which corresponds dorsally to the falciform ligament ventrally. The spleen is borne upon the outside of the hepato-oesophageal mesentery. The liver therefore underlies a considerable cavity which is largely separate from the rest of the abdominal cavity, the walls of which are formed by the various mesenteries attached to the liver. Anteriorly this cavity extends beyond the liver, and reaches up to the wall of the pericardium; its boundaries are shown by the dotted line in the accompanying drawing (text-fig. 28, p. 300). Its wall is very strong and tough. Posteriorly the mesenteries supporting the ovaries and the oviducts are not attached separately to the body-wall. The arrangement is as follows:-In the middle line is the mesentery supporting the gut, which is low in the rectal region where the gut is straight, and is higher anteriorly where the gut has a more sinuous course. It ends anteriorly upon the ventral surface of the liver on the right side of the gall-bladder, beyond which it does not extend. It is parallel to the falciform ligament, which is attached on the |