1881.] MR. W. A. FORBES ON THE KOALA.. 189 



The ovaries are rounded ovals in shape, considerably depressed, 

 and measurin£r about -15 inch along their greatest extent. Tliey 

 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 liiie 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 dehcate 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, some- 

 what compressed nipple-like eminence, forming the os tincce, 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 tinccB 

 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 065 inch, measured in a straight line ; that of the culs-de- 

 sac about U"45 inch. 



The urino-genital sinus is a tube, with moderately thick walls 

 and longitudinally plicated mucous membrane, of TS 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 de- 

 veloped 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 pre- 

 served 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 iu the sizes of 



