198 EXPERIMENTS WITH SPECTRUM. 



98 9ii 



The porcelain and yellow glass seemed, therefore, 

 to affect the ants almost equally, 



I then put two ants on a paper bridge, the ends 

 supported by pins, the bases of which were in water. 

 The ants wandered backwards and forwards, endea- 

 vouring to escape. I then placed the bridge in the 

 dark and threw the spectrum on it, so that succes- 

 sively the red, yellow, green, blue, and violet fell on the 

 bridge. 



The ants, however, walked backwards and forwards 

 without (perhaps from excitement) taking any notice of 

 the colour. 



I then allowed some ants [Lasius niger) tc find 

 some larva;, to which they obtained access over a 

 narrow paper bridge. When they had got used to it, 



