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Show 828 MR. P. E. BEDDARD ON THE [Dec. 3, there has been but one general account of the anatomy of tbe soft parts since the year 1825, when it was studied by Mayer \ who did not, however, direct attention to the special matters upon which I desire to report in the present communication. Mayer dissected three individuals, and he remarked upon the fact that in all of them the alimentary canal for the greater part of the intestinal region was beset with numerous small spherical cysts, which were mistaken by his predecessor Permin for glands appended to the alimentary tract, but which were recognized by Eudolphi as encysted Nematodes. There is no doubt about this identification, and I found them present in large numbers in both m y specimens. It is remarkable to find a parasite so invariably and so numerously present in its host, though there are other similar instances, such as the Gregarines in the sperm-sacs of the common Earthworm. Mayer's paper deals not only with the abdominal viscera, but also with the skeletal and muscular systems. There is, however, an earlier paper 2 which is not without value; in the plates appended to this are illustrations of several of the viscera isolated from their surroundings. More recently Khnckowstrom andGronberg3 have described and figured the structure of the skin, the larynx, the blood-vessels and the brain, besides some of the other viscera more or less incidentally. The two main lobes of the liver4 are absolutely separated from each other, the entire chamber enclosed by the suspensory ligaments of the anterior abdominal veins intervening. Along one margin each of the two lobes is firmly attached to the suspensory ligament of the abdominal vein, to the " diaphragm " and to the lung. The left half of the liver is rather larger than the right, and is partly divided into two lobes. The globular gall-bladder is associated with the right half of the liver; it is partly covered over by it, and lies in close contact with the membrane supporting the anterior abdominal vein. The anterior abdominal vein, instead of being firmly attached to the ventral parietes, is borne at the angle of a membrane which is V-shaped in transverse section. This membrane, however, in the hinder part of the body-cavity at any rate, seems to be merely the slightly displaced peritoneum, which in that region of the body is not closely adherent to the muscular parietes. On pulling the vein the whole of the peritoneum lining the body-cavity posteriorly readily came away. Anteriorly the state of affairs seems to be a little different. The abdominal vein is still supported by a V-shaped membrane, but the two folds of membrane are firmly attached to the parietes. So far m y description applies to the female example of the frog dissected by me. In the male the abdominal vein appeared posteriorly to stand out freely from the body-wall. I 1 " Beitrage zu einer anatomische Monographic der Bana pipa," Verh. k. Leon Car. Akad. 1825, p. 527. 2 Breyer, ' Observationes Anatomicas circa i<fbr\ca,m Rana pipce' (Berl., 1811). 3 " Zur Anatomie der Pipa americana," Zool. Jahrb. Abth. f. Anat. 1894. * There is a small separate third lobe. See Zool. Jahrb. loc. cit. pi. 39. fig. 7. |
