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Show 1877'.] ANATOMY OF HY.ENA CROCUTA. 37 J of the depression being covered with hair of the same colour as the surrounding parts. In this depression are situated two apertures, that of the anus, and that of the anal-gland pouch, the latter being situated between the former and the root of the tail. The lower margin of the anus is placed an inch above the scrotal pouches, the skin between them being black. The anus is separated by a transverse fold of integument from the anal-gland pouch. The skin of the latter is smooth and devoid of hair, with the exception of three small tufts, one of which springs from the middle of the upper wall of the pouch, and one from each of its inferior external angles. At the bottom of the pouch, on either side of the middle line, is a single aperture of sufficient size to admit a quill. These are the openings of the ducts of two large anal glands ; and stretching across the bottom of the pouch from one of these openings to the other is a transverse line of perforations which correspond to the excretory ducts of a number of small isolated glandules to be subsequently described. Having now described the appearances of the external parts, I pass on to the description of the Internal Organs. Rectum and Anal Glands.-The walls of the rectum are thick, being provided with a strong layer of longitudinally arranged muscular fibres. It has the usual relation to neighbouring viscera, and terminates immediately below the pouch which receives the excretory ducts of the anal glands. This pouch has a transversely oval form, is 2\ inches in breadth, and is depressed from the level of the perineum to the depth of \\ inch. The anal glands which pour their secretion into it are two in number; but in addition to these there is a belt of isolated glandular follicles which extends across the bottom of the pouch. Each anal gland is situated above aud to the outer side of the rectum, and has, when denuded of the surrounding connective tissue, a botryoidal appearance, by reason of the presence of a number of little grape-like projections on its surface. Each is roughly pyriform, and has the apex directed forward and upward, the base backward and downward. The inner side of each gland is applied to the corresponding angle of the anal pouch ; and from this surface of the gland the duct is given off to open into the pouch as previously described. Each of the glands measures 2\ inches from base to apex, and lj inch in diameter at the base. When cut open, each is seen to consist of a thick glandular wall, enclosing a single cavity of large size which communicates by means of the opening already described with the anal-gland pouch. The cavity of the gland was filled with a thick yellowish secretion, evidently the product of the glandular walls, of the consistence of butter, and having a very offensive smell. A quantity of muscular fibres apparently continuous with those of the sphincter ani surrounds each gland, and evidently acts as a compressor. The belt of glandular follicles above referred to as extending across the bottom of the anal-gland pouch, consists of a large number of isolated glands, each about |