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Show 302 MR. F. E. BEDDARD ON THE [Nov. 3, sheet of membrane just referred to, is a foramen in the hepato-pulmonary membrane, which, whether normal or abnormal, is certainly natural. It is a foramen with a perfectly clear margin as seen with a lens, and four to five millimetres across. In the drawing a probe is represented inserted in this foramen. On the left side of the body the membrane which bears the orifice of the oviduct arises also from the edge of the liver anteriorly. This state of affairs, which has been described by others, is not apparent in the smaller, male, individual. In this Salamander the base of the lung is closely attached to the lateral parietes on both sides of the body by a tough and very short membrane. There is no trace whatever of a fold of membrane arching over this and bearing the mouth of the oviduct. Evidently, therefore, the existence of this fold is associated with the oviduct, for the smaller animal was fully mature. The sperm-duct could be traced forward to below the shelter of the lung, i. e. where the latter fills up the space between the liver and the parietes. Here the membrane supporting it curves round in a semicircle to the right as in the larger individual, but there was no trace of the oviduct along the semicircular curve. On the other hand, what I take to be the end of the sperm-duct lay in the same straight line with the rest of the duct*. I may remark, furthermore, that the extent and depth, as shown by passing a probe above it, of the semicircular membrane is greater proportionately in this male individual. A bristle tipped with sealing-wax could be passed forwards as far as to a point beneath the pericardium. This extension forwards of the body-cavity then comes to be obliterated in the female, or indeed possibly in course of growth, perhaps owing to the pressure of the lung. On the left-hand side of the body I found precisely the same state of affairs. § The Heart. The heart, which has been described by Osawa f more accurately than by others, lies in a spacious pericardium which is roughly of a circular form, and proved to have the following dimensions : greatest diameter 65 mm., greatest length 6"5 m m . The heart does not by any means completely fill this pericardium. As to the general shape of the heart, the ventricle is rhomboidal, the posterior angle of the rhomboid lying a little to the right of the entrance of the vena cava inferior. The right-hand angle of the rhomboid is tied down by a gubernaculum (text-fig. 29, G ) , not figured by Osawa, which is attached partly to the wall of the pericardium, and partly to the right vena cava superior. The gubernaculum is broad and can be seen, by passing a probe beneath it and then # The sperm-ducts end anteriorly in a small flattened projecting body only attached by one end to the membrane which supports it. I find a precisely similar body in the large female, but entirely unconnected with any further rudiment of the male-duct. This is referred to on p. 315, in connection with the termination of the Arterire comites aorta. t " Beitrage zur Anatomic des .lapaniscben Riesensalamanders," Mitth. Medicin Facult. k. Japan. Univ. v. p. 221 (1902). |