3/8 THE COEPUS LUTEUM OF DASmiUS, 



was seen previously that immediately after rupture of the follicle 

 the blood vessels of the theca folliculi become enlarged at ^ arious 

 points round the circumference of the follicle. At these points 

 a sprouting of the connective tissue takes place. The cells 

 enlarge, their nuclei increase in size, and some show karyokinetic 

 figures. A new formation of blood vessels takes place at the 

 same time, and these new blood vessels, with the connective 

 tissue cells i-ound them, wedge their way through the membrana 

 propria and cells of the membrana granulosa toward the cavity 

 of the follicle. This process goes on at the various points so that 

 the whole early corpus luteum is represented by a lobulated 

 structure (see tig. 11). 



Next, the connective tissue bursts through the membrana 

 granulosa comi^letely, and reaches the cavity of the follicle, which 

 it fills with loose connective tissue cells with processes which 

 join, and form a connective tissue framework that fills the cavity 

 of the ruptured follicle. In some cases, besides the connective 

 tissue cells which are triangular in shape, there are found larger 

 rounded cells with one or two nuclei, a granular protoplasm and 

 a distinct wall. These often lie free in the cavity, singly or in 

 masses, and man}' of them are seen in close proximity to bands 

 of young fibrous tissue or between the ordinary connective tissue 

 cells. They are probably "fibroblast" cells (see fig. 11). 



The rate of metamorphosis of the cells of the membrana 

 granulosa into those of the corpus luteum varies in its rapidit}'. 

 Generally it does not begin until the connective tissue irrupts- 

 into the cavit}' of the follicle. In a few cases the cells of the 

 membrana granulosa undergo their metamorphosis, and almost 

 completely fill the cavit}- before the connective tissue reaches it. 

 At first the cells of the membrana granulosa, on being released 

 from intrafollicular pressure, are crowded together by the collapse 

 and corrugation of the follicular wall. The cells nearest the 

 membrana propria and the irrupting blood vessels, are the first 

 to show an alteration in character. Their cytoplasm swells and 

 their nuclei become more regularly arranged than the nuclei placed 

 more centrally. Many of them are oval in shape, and have the 



