102 LEO LOEB. 



Hypotypical ovaries of the first order. A small vacuolar corpus 

 luteum. Hypotypical uterus. In this case again delayed ovula- 

 tion. 



Guinea Pig No. n. Was found dying. Hypotypical ovaries 

 of second order. Small vacuolar retrogressing corpora lutea. 

 Uterus hypotypical. Delayed ovulation. 



Guinea Pig No. ij. Found dead. Some postmortem changes. 

 Hypotypical ovaries of second order. Small vacuolar retro- 

 gressing corpora lutea. Hypotypical uterus. 



In this series all the guinea pigs show hypotypical ovaries 

 after a loss of weight of approximately 26-31 per cent, in the 

 course of one to two weeks. In Guinea Pig No. 13 we find in a 

 period of five days a loss of 13 per cent., but in the last two days 

 before death a further considerable loss of weight had in all 

 probability occurred. In 2 cases (Guinea Pigs Nos. I and 2) we 

 do not yet find hypotypical ovaries. In the first animal, how- 

 ever, abortion took place toward the end of the experiment. 

 We may attribute the abortion to the lack of a sufficient quantity 

 of food. Abortion is not usual among guinea pigs without a 

 preceding experimental interference. Following the abortion a 

 new ovulation had not yet taken place at the time of examination. 

 In the second animal (Guinea Pig No. 2) ovulation had taken 

 place shortly before the conclusion of the experiment, but there 

 were indications of a beginning hypotypical condition of the 

 ovaries following the ovulation. In these two cases we have in 

 the first place to deal with somewhat heavier animals, and 

 secondly, a slightly smaller relative loss of weight was distributed 

 over a longer period of time. It is probable that the greater 

 initial weight of these guinea pigs caused a greater resistance 

 to the underfeeding; their general condition was less affected 

 by the underfeeding and consequently we find as yet no marked 

 changes in ovaries and uterus. In the five control animals of 

 this series the sexual cycle took its normal course; pregnancy as 

 well as ovulation proceeded normally. 



II. SERIES. (See Table III.) 



Five guinea pigs were used in this experiment. Guinea Pig 

 No. i served as control, the other four were undernourished and 



