References 117, 



Dice, L. H. The factors determining the verti- 

 cal movements of Daphnia. Jour. Animal Behavior, 

 4, 229, 1914. 



EsTERLY, C. O. Reactions of copepods to light 

 and gravity. Am. Jour. Physiol., 18, 47, 1907. 



EwALD, W. F. On artificial modification of light 

 reactions and the influence of electrolytes on photo- 

 taxis. Jour. Exp. Zool., 13, 591, 1912. 



Groom, T. T. and Loeb, J. Der Heliotropis- 

 mus der Nauplius von Balanus perforatus und die 

 periodischen Tiefenwanderungen pelagischer Tiere. 

 Biol. Cent., 10, 160, 1890. 



Harper, E. H. Behavior of the phantom larva 

 of Corethra plumicomis. Jour. Comp. Neur. Psych., 



i7> 435. 1907- 

 Holmes, S. J. (i) Phototaxis in the Amphi- 



poda. Am. Jour. Physiol., 5, 211, 1901; (2) Pho- 

 totaxis in Volvox. Biol. Bull., 4, 319, 1903; (3) 

 The reactions of Ranatra to light. Jour. Comp. 

 Neur. Psych., 15, 305, 1905; (4) The reactions of 

 mosquitoes to light in different stages of their life 

 history. Jour. Animal Behavior, i, 29, 191 1. 



Jackson, H. H. T. The control of phototactic 

 reactions in Hyalella by chemicals. Jour. Comp. 

 Neur. Psych., 20, 259, 1910. 



Loeb, J. Ueber kiinstliche Umwandlung positiv 

 heliotropischer Tiere in negativ heliotropische und 

 umgekehrt. Arch. ges. Physiol., 54, 81, 1893. 



Mast, S. O. (i) Light reactions in lower or- 

 ganisms, n. Volvox globator. Jour, Comp. Neur, 



