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Show 1881.] MR. W. A. FORBES ON THE KOALA. 189 The ovaries are rounded ovals in shape, considerably depressed, and measuring about -45 inch along their greatest extent. They are cut up by three or four sinuous fissures ; each of these lobes is further subdivided into ovisacs, which are of large size for a Mammal, though nothing like so big as the large ones figured by Prof. Owen in Phascolomys. The ovaries are enveloped to some extent by the fimbriated ends of the Fallopian tubes, and are enclosed, in common with these, in pouches of delicate peritoneum. The fimbriated ends of the oviducts are attached narrowly to the posterior part of the ovary; they extend hence for about 0*5 inch to the ostium abdo-minale. The Fallopian tubes are little bent, and are of small calibre, passing gradually into the larger, somewhat fusiform uteri, which, as usual in the Marsupials, are quite separate from each other ; muscular, thick-walled, and nearly straight, these open on a prominent, somewhat compressed nipple-like eminence, forming the os tinea?, by a small pore. The total length of the Fallopian tubes and uteri is about 1*3 inch from the ostium at the commencement of the former. The vaginae are also two in number, each being bent outwards in a simple curve, and not communicating with its fellow at any point. The lower part of each vagina is thick-walled, with but a small central cavity, which opens into the urino-genital sinus by a small pore, 0'2 inch above the opening of the vesical urethra. Above they are thin-walled; and from the internal side is developed a blind cul-de-sac, also thin-walled, communicating only with the vagina of its own side and the corresponding uterus, there being a median septum between the two culs-de-sac. No opening from the latter into the urino-genital sinus exists in either specimen I have examined. From the os tinea? there is prolonged downwards on each side a slightly elevated fold of the mucous membrane, which separates off the vagina proper from the more medianly placed cul-de-sac. Both vaginae and culs-de-sac are lined by smooth mucous membrane, with slight longitudinal rugae. The two uteri, as well as the vaginae and their appendices, are united together by peritoneum. The two ureters penetrate this to open into the neck of the bladder, beyond the termination of the vaginal culs-de-sac. The length of the vaginae is about 0'65 inch, measured in a straight line ; that of the culs-de-sac about 0'45 inch. The urino-genital sinus is a tube, with moderately thick walls and longitudinally plicated mucous membrane, of 1*3 inch in length. It communicates below by a considerable aperture with the rectum, and the cloaca so formed is surrounded by a common fold of muscles and integument. A small, flattened, linguiform clitoris, not free at its apex, with two grooves above and about 0-2 inch long, is developed on the anterior wall of the cloaca, beginning at the level where the rectum and urino-genital canal meet. A second specimen examined-an adult female that has been preserved in spirit, and which, judging from the condition of its mammae, has been a mother-shows exactly the same relations of these parts as that here described, the only differences being in the sizes of |