138 DAVID DAY WHITNEY 



LITERATURE CITED 



Shull, A. F. 1911 Studies in the life cycle of Hydatina senta. II. The role 

 of temperature, of the chemical composition of the medium, and of 

 internal factors upon the ratio of parthenogenetic to sexual forms. 

 Jour. Exp. Zool., vol. 10, no. 2, pp. 117-166. 



1912 Studies, etc. III. Internal factors influencing the propor- 

 tion of male-producers. Jour. Exp. Zool., vol. 12, no. 2, pp. 283-317. 



1913 Eine kiinstliche Erhohung der Proportion der Mannchenerzeuger 

 bei Hydatina senta. Biol. Centralb., Bd. 33, Nr. 9, Sept. 20, pp. 

 575-576. 



1915 Periodicity in the production of males in Hydatina senta. Biol. 

 Bull., vol. 28, no. 4, pp. 187-197. 



Shull, A. F. and Ladoff, S. 1916 Factors affecting male-production in 

 Hydatina. Jour. Exp. Zool., vol. 21, pp. 127-161. 



Whitney, D. D. 1907 Determination of sex in Hydatina senta. Jour. Exp. 

 Zool., vol. 5. 



1910 The influence of external conditions upon the life cycle of Hy- 

 datina senta. Science, N. S., vol. 32, no. 819, Sept. 9. 



1914 The production of males and females controlled by food con- 

 ditions in Hydatina senta. Science, N. S., vol. 39, no. 1014, pp. 832- 

 833, June 5. ■ 



1914 The influence of food in controlling sex in Hydatina senta. 

 Jour. Exp. Zool., vol. 17. pp. 545-558. 

 Whitney, D. D. 1916 The control of sex by food in five species of rotifers. 

 Jour. Exp. Zool., vol. 20, pp. 263-296. 



