278 SrE JOHN LUBBOCK ON ANTS, BEES, AND WASPS. 



Experiments sJioiving how Ants are affected by different coloured 

 Lights and Media. 



From the observations of Sprengel there could of course be 

 little, if any, doubt, that bees are capable of distinguishing colours > 

 but I have in my previous papers read before the Linnean Society 

 recorded some experiments which put the matter beyond a doubt. 

 Under these circumstances, I have been naturally anxious to as- 

 certain, if possible, whether the same is the case with ants. I 

 have, however, found more difficulty in doing so, because, as shown 

 in the observations just recorded, ants find their food so much 

 more by smell than by sight. 



I tried, for instance, placing food at the bottom of a pillar of co- 

 loured paper, and then moving both the pillar and food. The pillar, 

 however, did not seem to help the ant (lasius niger) at all to find her 

 way to the food. I then, as recorded in my previous paper, placed 

 the food on the top of a rod of wood 8 inches high, and when the 

 ant knew her way perfectly well to the food so that she went 

 quite straight backwards and forwards to the nest, I found that 

 if I moved the pillar of wood only six inches, the ant was quite be- - 

 wildered, and wandered about backwards and forwards, round and 

 round, and at last only found the pillar, as it were, accidentally. 



Under these circumstances, I could not apply to ants those 

 tests which had been used in the case of bees. At length, how- 

 ever, it occurred to me that I might utilize the dislike which ants, 

 when in their nests, have to light. Of course they have no such 

 feeling when they are out in search of food ; but if light is let in 

 upon their nests, they at once hurry about in search of the darkest 

 corners, and there they all congregate. If, for instance, I unco- 

 vered one of my nests and then placed an opake substance over 

 one portion, the ants invariably collected in the shaded part. 



I procured, therefore, four similar strips of glass, coloured re- 

 spectively green, yellow, red, and blue, or, rather, violet. The 

 yellow was rather paler in shade, and that glass consequently 

 rather more transparent than the green, which, again, was rather 

 more transparent than the red or violet. I then laid the strips 

 of glass on one of my nests of Formica fusca containing about 

 170 ants. These ants, as I knew by many previous observations, 

 seek darkness, and would certainly collect under any opake sub- 

 stance. 



1 then, after counting the ants under each strip, moved tlie 

 colours gradually at intervals of about half an hour, so that each 



