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Show 1905.] ANATOMY OF THE LEATHERY TURTLE. 3 1 5 together that their backwardly directed points form practically the whole of the exposed inner surface. Between the larger processes and upon their bases are smaller ones of various sizes. The processes are different in shape in the various regions of the oesophagus. Near the pharynx they have a spur like, slender, and slightly flattened form and are always single. Further down they become far stouter with a thick conical point, and are often bifid or even trifid (text-fig. G9). The horn cap has a very definite limit towards the base of the process, beyond which the surface of the shaft is relatively soft and more or less wrinkled. In Chelone, so far as I have seen, the processes are far more regular in form and are always single. The tubular part of the stomach (R. C. S. Museum, Physiol. Series 516 A) is partially divided into compartments by thirteen or so low irregular transverse folds, none of which is, however, sufficiently marked in this specimen to warrant the expression " diaphragms perforated in their centre " used by Vaillant in his description of them. The inner surface of the stomach is smooth. The intestine (text-fig. 70, int.) passes at first in an anterior direction from the pylorus to the median border o£ the left lobe of the liver. It then turns to the right along the dorsal surface of the isthmus to the outer border of the right lobe. The bile and pancreatic ducts open into this transverse segment, and here also lies the transversely elongated pancreas, as in Testudo. Near the outer border of the right lobe of the liver, the mesentery increases very much in extent and the gut is thrown into numerous coils, that occupy the right side of the abdominal cavity. The small rounded spleen (text-fig. 70, spl.) is lodged in a fold of the peritoneum at the root of this mesentery under cover of Text-fig. 69. Dermochelys coriacea, oesophagus. A. Bifid process from the middle part. B. Trifid process from the lower end. Stomach and Intestine. |