454 RUPTURE OF GRAAFIAN FOLLICLES. [sect. 204. 



§ 204. Detachment and Re- formation of the Ovula. — Corpora 

 Lutea. — [From the commencement of puberty onwards to the 

 period of involution, there takes place in the ovaries a continual 

 detachment of the ovula by the dehiscence of the Graafian fol- 

 licles; and this occurs equally in married women and virgins, 

 independently of sexual intercourse. It takes place especially at 

 the menstrual period, although, under circumstances not yet accu- 

 rately ascertained, it may, and frequently does, occur at other 

 times. In animals, the same process presents itself at the period 

 of ' heat/ but here sexual union appears to be a more necessary 

 condition for its completion; here, also, the anatomical changes 

 can be traced in great perfection, whilst, in the human female, the 

 opportunity of making such observations is much more seldom 

 presented. 



"When the Graafian follicles approach the period of bursting, 

 they gradually enlarge until they acquire a circumference of 4 to 

 6 lines and upwards, and they come nearer and nearer to the 

 surface, until at last they project beyond it in a wart-like or 

 hemispherical form, being only covered by a thin pellicle of the 

 extremely attenuated tunica albuginea, with its peritoneal covering. 

 At the same time, their vessels increase to an unusual degree, and, 

 by continual exudation from them, the liquor folliculi becomes 

 more and more abundant ; meanwhile, the fibrous coat of the 

 follicle, at the bottom and lateral aspect, but not where the ovulum 

 is situated, becomes thickened internally, and the membrana gra- 

 nulosa also swells somewhat, aud possesses larger cells (measuring 

 up to o'Oi'" in diameter). When these processes have* gone on to 

 a certain extent, the thin opposing membranes are no longer able 

 to withstand the continued and increasing pressure from the in- 

 terior of the follicle ; they give way at the thinnest and most 

 prominent point, exactly where the ovulum is situated. The Fal- 

 lopian tube, then, applying itself directly over the follicle, receives 

 the ovule on its escape, surrounded by the cells of the germinal 

 eminence. The Graafian follicle, however, has not at this stage 

 completed its career, for it becomes the seat of a series of for- 

 mations, partly new, in consequence of which it becomes converted 

 into the so-called corpus luteum, and ultimately disappears alto- 

 gether. 



These yellow bodies (corpora luted) are best marked when con- 

 ception and pregnancy follow upon the detachment of the ovulum, 

 and in their most developed condition, they appear as roundish, or 

 oblong firm bodies, generally of larger size than the previous fol- 



