TEMPEEATURE SENSES IN FROG S SKIN 



97 



The upper clamp held a large tube through which common steel 

 shot could be easily rolled. This tube was adjustable in the 

 clamp so that its angle of inclination could be easily changed. 

 When a tactile stimulation was to be made the frog was suspended 



Fig. 



shot. 



1 Apparatus for suspending frog and for tactile stimulation by falling 



with its foot resting very lightly on the support, and with the 

 glass tube trained upon the spot to be stimulated, so that when 

 the shot was rolled through the tube it would strike the proper 

 surface of the foot. The distance between the surface of the 

 foot and the end of the tube, the inclination of the tube at 45°, 



