562 GENERATION AND DEVELOPMENT. 



canal by which each Fallopian tube is traversed is narrow, 

 especially at its point of entrance into the uterus, at which it 

 will scarcely admit a bristle ; its other extremity is wider, and 

 opens into the cavity of the abdomen, surrounded by the zone 

 of fimbrise. Externally, the Fallopian tube is invested with 

 peritoneum ; internally, its canal is lined with mucous mem- 

 brane, covered with ciliary epithelium (p. 37) : between the 

 peritoneal and mucous coats, the walls are composed like those 

 of the uterus, of fibrous tissue and organic muscular fibres 

 (pp. 456-7). 



The uterus (u, c, Fig. 206) is a somewhat pyriform, fibrous 

 organ, with a central cavity lined with mucous membrane. In 

 the unimpregnated state it is about three inches in length, two 

 in breadth at its upper part, or fundus, but at its lower pointed 

 part or neck, only about half an inch. The part between the 

 fundus and neck is termed the body of the uterus; it is about 

 an inch in thickness. The walls of the organ are composed of 

 dense fibro-cellular tissue, with which are intermingled fibres 

 of organic muscle : in the impregnated state the latter are much 

 developed and increased in number. The cavity of the uterus 

 corresponds in form to that of the organ itself: it is very small 

 in the unimpregnated state ; the sides of its mucous surface 

 being almost in contact, and probably only separated from 

 each other by mucus. Into its upper part, at each side, opens 

 the canal of the corresponding Fallopian tube: below, it com- 

 municates with the vagina by a fissure-like opening in its neck, 

 the os uteri, the margins of which are distinguished into two 

 lips, an anterior and posterior. In the mucous membrane of 

 the cervix are found several mucous follicles, termed ovula or 

 glaudulse Nabothi: they probably form the jelly-like substance 

 by which the os uteri is usually found closed. 



The vagina is a membranous canal, six or eight inches long, 

 extending obliquely downwards arid forwards from the neck 

 of the uterus, which it embraces, to the external organs of 

 generation. It is lined with mucous membrane, which, in the 

 ordinary contracted state of the canal, is thrown into trans- 

 verse folds. External to the mucous membrane, the walls of 

 the vagina are constructed of fibro-cellular tissue, within which, 

 especially around the lower part of the tube, is a layer of 

 erectile tissue. The lower extremity of the vagina is embraced 

 by an orbicular muscle, the constrictor vaginae ; its external 

 orifice, in the virgin, is partially closed by a fold or ring of 

 mucous membrane, termed the hymen. The external organs 

 of generation consist of the clitoris, a small elongated body, 

 situated above and in the middle line, and constructed, like 

 the male penis, of two erectile corpora cavernosa, but unlike 



