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Show 1879.] ANATOMY OF HV.ENA CROCUTA. 83 radiated somewhat after the manner observed in the gizzard of a bird and the same appearance is noticeable in our specimen. This tendinous arragement, however, is confined to the surface of the organ, and does not extend into the wall. Professor Flower, in accordance with differences in appearance of its mucous membrane, describes three distinct portions of the stomach in Proteles; and a similar subdivision may be adopted in describing that of Hycena crocuta. In the first, or cardiac portion of the organ, the mucous membrane is thrown into well-marked rugae, which are not arranged in any regular manner, but, uniting at various points with one another, give rise to a convoluted appearance somewhat resembling the gyri of the cerebrum. They are more irregularly disposed at the entrance of the oesophagus than elsewhere, and are here continuous with the longitudinal rugae of that tube. In respect of the rugose character of this portion of the gastric mucous membrane, H. crocuta differs from Proteles, in the stomach of which these rugae are absent. Corresponding to the middle third of the stomach, the mucous membrane is thrown into rugae of larger size than elsewhere. These rugae lie parallel to the long axis of the organ, and are united here and there by means of smaller transverse folds. Along the great curvature the large longitudinal folds are better marked than on the small curvature of the stomach. The mucous membrane of the duodenal third of the. stomach is less rugose than that of any other portion, such rugae as are present being found in relation to the curvatures of the organ, wbilst the anterior and posterior walls of the stomach are quite smooth. Every portion of the gastric mucous membrane in the intervals of the larger rugae presents a delicate reticulate and glandular appearence. The pyloric orifice is extremely small, and in the specimen examined measured only g of an inch in diameter. The valve is annular in form, and not cres-centic as in Proteles. It will be seen from what has been said, that, in respect of the form and character of the stomach, but little difference is observable between the three species of Hycena when they are compared with one another or with Proteles. Small Intestine.-This portion of the gut measures 32 feet 6 inches in length. Its diameter is not uniform, but presents a number of constrictions, which are distributed at irregular intervals along its entire course. As a rule it measures about one inch in diameter ; but where constrictions occur it does not exceed half an inch. Throughout its course its mucous membrane is covered with villi. The Peyerian patches are eight in number, and vary much in size, the smaller being found towards the commencement of the intestine, whilst the largest, which measured 9 inches in length, was situated toward the lower end of the ileum. It is worthy of note that in Proteles the number of these patches is the same as in H. crocuta. In II. striata, according to Meckel1, they do not exceed twelve in number. Great intestine.-The caecum measures 6 inches in length, and agrees closely as regards its form with that figured by Daubenton in H. striata. In the latter species, according to the author named, 1 Loc. cit. p. 706. 6* |