170 



PHYSIOLOGY 



CHAP. 



As the result of the bursting of the Graafian follicle there 

 almost always occurs a haemorrhage, which is generally slight, 

 and is due to laceration of the vessels of the follicular theca ; 

 and the blood collects and coagulates in the cavity of the follicle. 

 Later, through the activity of the stratum granulosum of the 

 burst follicle, there is produced in its place a special organ, called 

 the corpus luteum. Owing to the expulsion of the contents of the 

 follicle, and the retraction of the follicular theca, the stratum 

 granulosum is reduced to a crinkled lamina which surrounds the 

 coagulated blood. This lamina increases constantly in thickness, 

 occupying a greater and greater part of the cavity of the old 



V 



Fio. 55. Section through a corpus luteum of the ovary of a woman who died at the fifth lunar 

 month of pregnancy. Magnified 6 diameters approx. (Kolliker.) nc, central connective 

 tissue ; I, stratum of lutein cells ; o, surface of ovary ; s, remains of extravasated blood and 

 hyaline masses ; v, blood-vessel ; c, remains of central cavity ; te, external tunic of follicle. 



follicle, whilst the coagulum is condensed and in part reabsorbed. 

 In this manner is formed a more or less spherical, yellowish-grey 

 body, the corpus luteum (Fig. 55). It attains a greater size than 

 that which the follicle had (1 to 2'2 cm.). The mass of the fully 

 developed corpus luteum is formed of lutein cells, so called because 

 they contain granules of lutein, which is a lipochrome soluble in 

 alcohol and ether, and like the fats staining black with osmic 

 acid (Fig. 56). From the follicular theca penetrate towards the 

 stratum of lutein cells numerous connective-tissue fibres, which 

 enclose the lutein cells in a delicate meshwork. The residual 

 parts of the extravasated blood are recognisable as hyaline masses 

 in which Virchow discovered the haematoidin crystals. 



After the twelfth day from the bursting of the follicle, if 



