THE CORPUS LUTEUM. 



609 



FIG. 169. 



GRAAFIAN FOLLICLE of the 

 human ovary ; recently 

 ruptured during menstru- 

 ation, and filled with co- 

 agulated blood; longitudi- 

 nal section. a. Tissue of 

 the ovary, containing un- 

 ruptured Graafian follicles. 

 b. Vesicular membrane of 

 the ruptured follicle, c-. 

 Point of rupture. 



its cavity, and may be easily turned out with the handle of a scalpel. 



It has sometimes a slight mechanical adhesion to the edges of the 



lacerated opening ; but there is no continuity of 



substance between them, and the clot may be 



everywhere separated by careful manipulation. 



The membrane of the vesicle presents a smooth, 



transparent, and vascular internal surface. 



Soon afterward an important change takes 

 place, both in the central coagulum and in the 

 vesicular membrane. 



The clot, which is at first large, soft, and gelat- 

 inous, begins to contract ; and the serum sepa- 

 rates from the coagulum proper. The serum is 

 absorbed by the neighboring parts ; and the clot, 

 accordingly, grows smaller and denser. At the 

 same time its coloring matter undergoes the 

 usual changes which follow extravasation, and 

 is partially reabsorbed together with the serum. 

 This second change is somewhat less rapid than 

 the former, but a diminution of color is usually 

 perceptible in the clot, at the expiration of two 

 weeks from the rupture of the follicle. 



The vesicular membrane at the same time 

 takes on an increased development, by which it becomes thickened and 

 convoluted, and tends partially to fill the cavity of the follicle. Its 

 hypertrophy and convolution commences earliest and proceeds most 

 rapidly at the deeper part of the follicle. From this point it becomes 

 thinner and less convoluted toward the surface of the ovary and the 

 edges of the ruptured orifice. 



At the end of three weeks, the hypertrophy of the vesicular mem- 

 brane has reached its maximum. The follicle has now become so altered 

 by the growth above described, and by the condensation of its clot, that 

 it presents the appearance of a solid body of new formation, and receives 

 the name of "corpus luteum," although its yellow color is not yet dis- 

 . tinctly developed. It causes a perceptible prominence on the surface 

 of the ovary, and may be felt as a rounded tumor, in the ovarian tissue, 

 nearly always somewhat flattened from side to side. It measures about 

 19 millimetres in length and about 12 millimetres in depth. On its 

 surface there is a minute cicatrix, the mark of the original rupture. 



On cutting it open at this time (Fig. 170), the corpus luteum is seen 

 to consist, as above described, of a central coagulum and a convoluted 

 wall. The coagulum is semi-transparent, of a gray or light-greenish 

 color, more or less mottled with red. The convoluted wall is about 

 three millimetres thick at its deepest part, and of an indefinite yellow- 

 ish or rosy hue, not very different in tinge from the rest of the ovarian 

 tissue. The convoluted wall and the contained clot lie in contact with 

 each other, without intervening organic connection ; and they may still 



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