No. ()29] B ABIT AT BKSPONSES OF WATER-STRIDER 485 



ments were carried on at Syracuse in the afternoon, at 

 which time there was considerable reflection of the rays 

 of the sun from the surface of the water. 



3. Responses When Facing Away from Pool.— The first 

 set of experiments deals with gerrids that were placed 

 on the ground one yard away from the margin of the 



