' 

 432 REPRODUCTION AND DEVELOPMENT 



children. It is from this, biologically speaking, that these new desires 

 and thoughts and emotions get their sweetness and their worth, as 

 indeed the normal woman finally learns to realize. 



Of all the new activity in the female organs the two new functions of 

 ovulation and menstruation are in a way probably the most essential, 

 the former in particular. It is not yet known how these are related 

 biologically, hence we describe them separately as two processes rather 

 than as parts of one. 



OVULATION is the process in which a matured ovum breaks out of the 

 ovary and is started down the Fallopian tube toward the uterus. Every 

 lunar month at least one of the Graafian follicles makes its way to the 

 surface of the ovary, but just how this passage through the stroma occurs 

 and is controlled is not understood. When it arrives there and projects 

 beyond the general surface of the ovary, the outer walls of the follicle 

 may degenerate and give way, thus freeing the ovum and the plasma 



FIG. 246 



A sectional view of the left Fallopian tube, showing its numerous channels, its widely 

 spreading openings, and its close connection with the ovary. (Sappey.) 



about it in the follicle on the ovarian surface. The follicle's rupture 

 may come from its over-distent ion with lymph, from excessive congestion 

 of the ovarian stroma, or from the reflex active contraction of the ovarian 

 musculature in the excitement of coitus. The last-mentioned possi- 

 bility has been usually overlooked. The inner lining of the Fallopian 

 tubes, including the trumpet-shaped fimbrise, is ciliated, and the cilia all 

 wave so as to cause a slight but continuous stream of lymph down the 

 tubes toward the womb. If the fimbriated end of the tube embraces the 

 side of the ovary during ovulation, it is easy to see that the minute ovum 

 (0.2 mm. in diameter) would very probably be drawn into the wide 

 openings of the tube and, once started, be passed slowly along one of the 

 very narrow channels into the uterus. The rate of this passage averages 

 perhaps 20 mm. per day. In trying to define how this functional con- 

 nection between ovary and tube can take place so regularly (abdominal 

 pregnancies are relatively uncommon though by no means rare), it must 

 be kept in mind that there are no open spaces in the abdominal cavity, 



