Holmes, 77/^ Reactions of Ranatra to Light. 



313 



over towards it, the right legs are flexed and the left ones 

 extended (See fig. i). Pass the light over to the left side of 



Fig. I. Attitude of Ranatra when the right side is toward the light. 



the body and the back tilts over to the left, the left legs become 

 flexed and the right ones extended. For a short time after 

 coming out of its feint Ranatra will usually sway back and forth 

 as the light is moved over it without attempting to walk, but 

 soon it begins to follow the light, at first with slow and unsteady 

 steps, but later with more and more vigor, until finally its efforts 

 to go towards the light become almost desperate, and it 

 becomes oblivious to everything else. 



Besides the lateral swaying movements which Ranatra per- 

 forms when light is passed over the body from side to side there 

 are equally pronounced longitudinal swaying movements when 

 the light is passed back and forth along the axis of the body. 

 When the light is placed behind the animal the body is raised 

 up in front and the head held high in the air. Now place the 

 light in front, and immediately the body is lowered, and the 

 head bowed down, the grovelling attitude contrasting almost 



