208 EXPEUIMENTS WITH HOODWINKED ANTS. 



Forel, in some recent experiments, varnished over 

 the eyes of fifteen ants {Camponotus liijniperdus) and 

 put them with fifteen othern, which were left in their 

 normal condition, in a flat box with a glass top and 

 diviiied in the middle into two halves by a cardboard 

 division, which, houever, left room enont^h underneath 

 for the ants to pass freely from one half to the other. 

 After some other experiments, in the course of which 

 one of the varnished ants was accidentally killed, at 

 1 p.m. all the v.irnished ants and thirteen of the un- 

 varnished were in the right half of the box, and two 

 unvarnished in the left. He tlien placed over the 

 whole box two flat bottles containing water to inter- 

 cept heat-rays — over the right half a piece of cobalt 

 (violet) glass ; and over the left, a flat bottle containing 

 a solution of esr'uline, which is quite transparent, but 

 cuts off the ultra-violet rays. At 1.55 the result was 

 as follows : — 



Under the escuUae. Under tlie cobalt. 



5 varnished. 9 varnished. 



13 noriuah 2 normah 



The esculine and cobalt were then transposed. At 

 2.3 the position was — 



Under the cobalt. Under the esculine. 



4 varnished. 13 varnished. 



3 normal. 12 normal. 



The esculine and cobalt were again transposed, and 

 one normal ant was accideutally wounded and removed. 

 At 3.8— 



Under the escQline. Under the cobalt. 



3 varnished. 12 varnished. 



11 normal. 3 normal. 



