REACTIONS OF WHIP-TAIL SCORPION TO LIGHT 275 



4. When subjected to light of 120 candle meters acting on 

 them from the side, the scorpions turned and moved away 

 from the light. The average deflection was 65.8 degrees. 



5. When subjected to balanced, opposed lights each delivering 

 an illumination of 120 candle meters, the average trail was 

 within 3.7 degrees of the norm to the line connecting the sources 

 of light. 



6. When started directly toward a light giving an illumination 

 of 120 candle meters, the scorpions turned and moved away from 

 the source. The average deflection was 140.4 degrees. 



7. Unilateral elimination of any part of the photoreceptive 

 mechanism caused an unbalancing of subsequent reactions. 



8. Light operates as a stimulus inducing kinetic and directive 

 responses both through changes of intensity and constant 

 intensity. 



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