856 



THEOKIES OF OVULATION. 



discharged ovum, with its adherent granulosa cells, and the liquor folliculi, are 

 caught by the funnel-shaped extremity of the tube (fig. 646). The ovum, when 

 discharged, is carried towards the uterus by the ciliated epithelium ( 433) of the 

 tube, and perhaps also partly by the contraction of its muscular coat. Ducalliez 

 and Kiiss found that, by fully injecting the blood-vessels, they could imitate the 

 erection of the Fallopian tube. Rouget points out that the non-striped muscle of 

 the broad ligaments may cause constriction of the vessels, and thus secure the 

 necessary injection of the blood-vessels of the Fallopian tube. 



PflUger's Theory. There are two theories as to the connection between ovulation or the 

 discharge of an ovum and the escape of blood from the uterine mucous membrane. Pfluger 

 regards the Moody discharge from the superficial layers of the uterine mucous membrane as a 

 physiological preparation or "freshening" of the tissue (in the surgical sense), by which it 

 will 1>' prepared to receive the ovum when the latter reaches the uterus, so that union can 

 take place between the ovum and the freshly-exposed surface of the mucous membrane, and 

 thus the ovum will receive nourishment from a new surface. 



Eeichert's Theory. This view is opposed to that of Reichert, Engelmann, Williams, and 

 others. According to Reichert's theory, before an ovum is discharged at all there is a sympa- 

 thetic change in the uterine mucous membrane, whereby it becomes more vascular, more 

 Hpongy, and swollen up. The mucous membrane so altered is spoken of as the membrana 

 decid an mensiruali8, and from its nature it is in a proper condition to receive, retain, and 

 nourish a fertilised ovum which may come into contact with it. If the ovum, however, be not 

 fertilised, and escape from the genital passages, then the uterine mucous membrane degener- 

 ates, and blood is shed as above described. According to this view, the haemorrhage from the 



uterine mucous membrane is a sign of the 

 non-occurrence of pregnancy; the mucous 

 membrane degenerates because it is not re- 

 quired for this occasion ; the menstrual blood 

 is an external sign that the ovum has not 

 been impregnated. So that pregnancy, i.e., 

 the development of the embryo in utero, is 

 to be calculated, not from the last menstru- 

 ation, but from some time between the last 

 menstruation and the period which does not 

 occur. 



In some cases the ovulation and the for- 

 mation of the decidua menstrualis occur 

 separately, so that there may be menstrua- 

 tion without ovulation, and ovulation without menstruation. 



Corpus Luteum. When a Graafian follicle bursts, it discharges its contents and collapses ; 

 in the interior are the remains of the membrana granulosa and a small effusion of blood, which 



soon coagulates. The small rup- 

 ture soon heals, after the serum 

 is absorbed. The vascular wall 

 of the follicle swells up. Villous 

 prolongations or granulations of 

 young connective-tissue, rich in 

 capillaries and cells, grow into the 

 interior of the follicle (fig. 651). 

 Colourless blood-corpuscles also 

 wander into the interior. At the 

 same time the cells of the granu- 

 losa proliferate, and form several 

 layers of cells, which ultimately, 



Lymph- 

 atics. 



Stroma of ovary. 



Outer layer of follicle. 

 Vessels between outer 

 layer and tunica propria. 



Folded and thickened 

 tunica propria. 



Fig. 650. 

 Fresh corpus luteum. 



Fig. 651. -pia 652 



Corpus luteum of cow ( x 1*). Lutein cells from the corpus luteum of cow. 



malted ^Y^^T^^^ ^ 1 ^^' under ^tty degeneration, lutein, ^ fatty 

 matter being formed, and it is this mass which gives the corpus luteum its yellow colour (fig. 



