ORIGIN OF THE CORPUS LUTEUM 149 



appears at times to close the orifice immediately, but in other 

 cases the follicular walls do not come together about the opening 

 at once; the tiny slit is first plugged by fibrin, and later closed 

 permanently by proliferation of its edges, much as described by 

 Strakosch ('15) in the human corpus luteum. From the minute 

 blood-vessels whose torn ends lie in the stigma there is often a 

 slight oozing of serum or of blood, so that the surface of the 

 ovaries at this time may be roughened by tags of pale or bloody 



Theca mUma, 



Thee a externa 



Giircmuloe.a 



Poirvt of fupt ure 



Fig. 8 Diagram of ruptured Graafian follicle (sow in heat, ova in tubes), 

 illustrating partial collapse without great infolding of walls. X 14. (Compare 

 with figure 9.) 



fibrin, sometimes forming temporary adhesions to the fimbriae of 

 the tubes. The entire ovaries and the tubes are usually much 

 congested during oestrus. 



On section, the follicular cavity is collapsed to a mere slit 

 in some cases, in others it is still partially distended, owing to the 

 continued presence of more or less of the follicular fluid. For this 

 reason, the size of the structure varies, but in general it is much 

 smaller than the mature unruptured follicle, its diameters vary- 



