Contributions to the morphology and development of the female urogenital organs in the marsupialia / by Jas. P. Hill.

  • Hill, Jas. P.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Contributions to the morphology and development of the female urogenital organs in the marsupialia / by Jas. P. Hill. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    opens on the ventral wall of the cloaca by a small aperture (Plate i., fig. 1, O.U.S.), situated from 3’5 to 5 mm. within the margin of the cloacal opening. Its lining is thrown into longi- tudinal ridges. The vaginal canals open together into its anterior end dorsally, while a short distance posteriorly the urethra opens on its floor under a slight median papilla. Also situated on the floor of the sinus some distance behind the urethral opening is the small clitoris. It lies in a distinct longitudinal depression, justwithin the margin of the openingof the sinus, and is bounded by lateral preputial folds which may be continued beyond the margin of the opening. In form the clitoris is bluntly cone-shaped, and measures from 1 '5 to 2 mm. in length by about 1 mm. in greatest breadth. It is attached over its whole extent, though exception- ally its apex maybe free and slightly bifid. It is stated by Owen and Brass that where the glans penis is bifurcate in the male, in the female the clitoris is likewise bifid, but this statement does not hold for Perameles. I am unable to discover any reference in the literature to the minute structure of the clitoris in Marsupials; the following facts may therefore be of interest. Shortly in front of the clitoris two ducts leave the floor of the urogenital sinus and run back in the ventral wall of the latter to enter the clitoris proper. The lumina of these canals may be continuous or interrupted, or the ducts may even be entirely solid in different females. They run back enclosed below by a horse-shoe-shaped band of erectile tissue. Posteriorly, towards its apex, the clitoris is divided into two halves by a median septum (Plate v., fig. 9, m.s.) each half containing one of the canals below which is a horse-shoe-shaped mass of erectile tissue {e.t.). Eventually the canals open on the surface of the organ shortly behind its apex (fig. 9, c.d.). In view of the above, it is interesting to note that according to Owen (8, p. 312) “in the Perameles lagotis not only is the glans [ penis] bifurcate, but each division is perforated and the urethral canal is divided by a vertical septum for about half an inch before it reaches the forked glans.”