AGE OF HUMAN EMBRYOS 



413 



in relation to the menstrual cycle by Ruge IP'' who gives the 

 following data: 



TABLE 3 



Ovulation occurred in the stage of proliferation, and always 

 during the first 14 days of the period. However, this stage does 

 not form a regular sequence of development during the first two 

 weeks, but the specimens were of unequal development and 

 could not be arranged in the order of time. It is impossible to 

 determine the time elapsing between ovulation and the formation 

 of the third stage of mature corpus luteum, but Meyer and Ruge 

 believe that always a number of days must intervene. Finally, 

 the stage of involution overlaps that of proliferation. At any 

 rate the work of Meyer and Ruge demonstrates that the fresh 

 corpus luteum as described by Fraenkel^^ appeared a number of 

 days before he thought it did, thus completely overthrowing 

 Triepel's assumption that the probable time of ovulation is on 

 the 19th day. According to Ruge, it occurs sometime during 

 the first 14 days of the menstrual month which supports the theory 

 I am advocating. 



These are all the reliable data I have been able to collect 



10 Ruge II, Carl 1913 Ueber ovulation, corpus luteum and menstruation. 

 Archiv fur Gynaekologie, Bd. 100. 



11 Fraenkel: Archiv fiir Gynaekologie, Bd. 91. 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 23, NO 2 



