EGG AND FEMALE ORGANS OF GENERATION. 



693 



seen to be somewhat triangular in shape, its two superior angles running 

 out to join the lower extremities of the Fallopian tubes. This portion 

 evidently consists of the cornua, which have been consolidated with the 

 body of the uterus, and enveloped in its thickened layer of muscular 

 fibres. 



Fig. 229. 



GENERATIVE OROAKS OF THE HUMAN FEMALE. a, a. Ovaries, ft, 6. Fallopian 

 tubes, c. Body of the uterus, d. Cervix, e. Vagina. 



The cavity of the body of the uterus terminates below by a con- 

 stricted portion, termed the os internum, by which it is separated from 

 the cervix. These two cavities are not only different from each other 

 in shape, but also in the structure of their mucous membrane and in the 

 functions which they perform. 



The mucous membrane of the body of the uterus in its usual condi- 

 tion is smooth and rosy in color, and closely adherent to the subjacent 

 muscular tissue. It consists of tubular follicles, ranged side by side, 

 and opening by distinct orifices upon its free surface. The secretion of 

 these follicles is destined for the nutrition of the embryo during the 

 earlier periods of its formation. 



The internal surface of the cervix, on the other hand, is raised in 

 prominent ridges, arranged usually in two lateral sets, diverging from a 

 central longitudinal ridge ; presenting the appearance known as the 

 "arbor vitae uterina." The follicles of this part of the uterine mucous 

 membrane are of a globular or sac-like form, and secrete a tenacious 

 mucus, which serves, during gestation, to block up the cavity of the 

 cervix, and thus to prevent the escape or injury of the egg. 



The cavity of the cervix uteri is terminated inferiorly by a second 

 constriction, the " os externum ;" and below this comes the vagina, 

 which constitutes the last division of the female generative passages. 



The accessory female organs of generation consist, therefore, of ducts 

 or tubes, by means of which the egg is conveyed from within outward. 

 These ducts vary in the degree and complication of their development, 



