

'05: 



' 5 











* *^ ♦it ii 



^ M 



s 



> 



^ ^ 



^ 

 ^ 



!i;*^ 



««^' 



■^s 



c 



Plate XIII. The vaginal cycle in the white rat. A, section of lining of the vagina. 

 The inner surface, from which cells are shed as seen in following pictures, is at the 

 right. B, cells shed into cavity of vagina during interval part of cycle. The larger 

 masses are the epithelial cells; the small rounded objets with gnarled nuclei are 

 white blood cells (leucocytes) . C, just before estrus. D, during estrus (at time of 

 ovulation) showing complete cornification, with loss of nuclei. The section of the 

 wall of the vagina pictured at A was taken at this time, and shows the cornified 

 cells in place, forming a clear layer at the right. E, at end of estrus, showing return 

 of leucocytes. All magnified about 650 times. From J. A. Long and H. M. Evans, 

 "The Estrous Cycle in the Rat," University of Ccdifomia Memoirs, No. 6. 



