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S. O. MAST 



toward the ocular side, in place of the abocular side, as it did 

 before when it was positive. These results were repeatedly 

 and consistently obtained, but in no instance did the activat- 

 ing response follow increase in illumination. Similar results 



Fig. 3 Outline of Amaroucium pellucidum tadpole with tail embedded in 

 vaseline, a, resting position; 6, position assumed in reaction to shadow by 

 specimen in photopositive state; c, position assumed in reaction to shadow by- 

 same specimen in the photonegative state, v, vaseline. Note that the tail bends 

 toward the ocular side when the tadpoles are negative and toward the abocular 

 side when they are positive. 



were obtained in many other observations under various condi- 

 tions. There is consequently no doubt but that in the tad- 

 poles of Amaroucium both positive and negative specimens 

 respond to reduction in luminous intensity by becoming active, 

 that the response in the two states differs in character, and that 

 they do not become active in either state when the intensity 



