9 2 



LEO LOEB. 



to carry out further experiments in order to throw additional 

 light on the causes of the hypotypical condition of the ovaries. 

 It occurred to us that a common cause might underlie all those 

 cases in which a local injury of the ovaries was not present, and 

 that lack of proper nourishment might be an important factor 

 in this form of temporary sterility. We therefore carried out 

 four series of experiments in which female guinea pigs received 

 the same kind of food as usual, viz., oats and a little grass or 

 green vegetables, but both in much reduced quantity. We shall 

 discuss our experiments in the inverse order in which they were 

 done. In all cases but one both ovaries were cut in serial 

 sections after the completion of the experiment. In one animal 

 only one ovary was cut serially. 



IV. SERIES. 

 Five guinea-pigs were used in this experiment. (See Table I.) 



TABLE I. 



IV. SERIES. 



Microscopic Examination. 



Guinea Pig A. Had lost 28 per cent, of its weight twelve days 

 after beginning of feeding experiment. 



In the ovaries: small and small to medium follicles. In the 



