1316 THE UKO-GENITAL SYSTEM. 



One or more small pedunculated cystic structures, called appendices vesiculosi 

 (O.T. hydatids of Morgagni), are often seen near the infundibulum of the uterine tube. 

 These are supposed to represent portions of the upper end of the Wolffian duct. 



The par-odphoron is a collection of rudimentary tubules also enclosed by the 

 layers of the mesosalpinx, but lying nearer the uterus than the ep-oophoron. 

 These very rudimentary tubules represent the paradidymis in the male, and are 

 derived from the part of the mesonephros which lies nearer the caudal end of the 

 body of the embryo. Though sometimes visible in the child at birth, the par- 

 oophoron in the adult can only be made out with the aid of a lens. 



UTERUS. 



The uterus, or womb, is a hollow, thick-walled, muscular organ placed within the 

 pelvis between the bladder in front and the rectum behind. The ova discharged 

 from the ovary enter the uterus through the uterine tubes, and, if fertilisation has 

 taken place, undergo their development within it. In form the uterus is somewhat 

 pear-shaped, the wide upper end of the organ projecting freely upwards and for- 

 wards into the pelvic cavity, while the lower more constricted part is connected 

 with the vagina. The usual length of the adult uterus (when non-pregnant) is 

 three inches, its greatest breadth is nearly two inches, and its maximum thickness 

 is about one inch. In the description of the uterus we distinguish between an 

 upper larger portion, somewhat flattened from before backwards, composed of 

 fundus and body, and a lower more cylindrical part called the cervix (Fig. 1032). 



The part of the uterus that lies above the level of a line joining the points of 

 entrance of the uterine tubes is called the fundus uteri. The fundus is convex 

 from before backwards and from side to side, its anterior and posterior aspects being 

 directly continuous with the anterior and posterior surfaces of the body of the organ. 



The corpus uteri, when seen from in front or from behind, has a somewhat 

 triangular outline, and lies below the fundus, with which it is continuous. The 

 base of the triangle is directed upwards and is formed by a line joining the lateral 

 angles of the uterus, or points of entrance of the uterine tubes ; and the sides of 

 the triangle correspond to the lateral borders of the uterus, which extend on 

 each side from the lateral angle to the cervix. The margo lateralis or lateral 

 border separates, on each side, the facies vesicalis (or anterior surface) from the 

 facies intestinalis (or posterior surface) of the body. Both these surfaces are 

 rounded, but the intestinal is much the more convex. The vesical surface rests 

 against the upper aspect of the bladder, from which usually it is separated only 

 by the layers of peritoneum forming the utero- vesical pouch. The intestinal 

 surface forms the chief part of the anterior wall of the deep recess situated 

 between the uterus and rectum, and is usually in contact with some part of the 

 small intestine or the pelvic colon. The broad ligament passes laterally on each 

 side of the uterus from the lateral border of the organ. 



The cervix uteri is cylindrical, and at its commencement it is sometimes 

 marked off from the body by a slight constriction. Its length is about one inch, and 

 its inferior end, tapering somewhat, enters the upper part of the vagina. The cervix is 

 attached to the margin of the opening in the vaginal wall, through which it passes, 

 and in thrs"way a portio supravaginalis is marked off from a portio vaginalis of the 

 cervix. In the vaginal portion of the cervix there is an opening the orificium 

 externum uteri (O.T. external os uteri) through which the cavity of the uterus com- 

 municates with that of the vagina. In a uterus which has not been pregnant 

 this opening is nearly circular, but in women who have borne children it is usually 

 a transverse slit with a somewhat irregular outline. In front of, and behind, this 

 opening the cervix forms two lips, an anterior and a posterior, the labium anterius 

 and the labium posterius. The anterior lip is thicker, and slightly more rounded ; it 

 is placed upon a lower level than the posterior lip, which is slightly longer and 

 thinner. The cervix enters the vagina through the upper part of its anterior wall 

 in such a manner that the external orifice of the uterus is directed backwards and 

 downwards against the upper part of the posterior vaginal wall (Fig. 1033). 



