REPRODUCTION 71 



mucus and with nuclei showing signs of pycnosis. Below this is the stratum 

 granulosum which, with the approach of estrus, becomes the stratum 

 corneum. Third is the stratum germinativum, some seven cell layers in 



%'•- ' 



• r«.*T^^K ' Leukocytes 





\\ 



l&X t^^X -^^-j'^ ih , 



stratum germinativum 

 polygonal cells 



■Stratum germinativum 

 basal cells 



-Lamina propria 



_J| Stratum germinativum 



polygonal cells 



Stratum germinativum 

 basal cells 



^ ' v-_ '.» ' T Lamina propria 



'^^^..df-m 



Fig. 38.— Photographs of vaginal epitheUum of a mouse in different stages of the 

 estrous cycle. A. Metestrus-2. B. Diestrus. {Frovi Clauherg.) 



thickness. During proestrus and early estrus the cells of the outer layer 

 are delaminated into the vagina, producing the characteristic nucleated 

 cell smear. The'degree of delamination is not uniform in all parts of the 

 vagina, so that prior to the onset of estrus the cornified layer may be fully 



