am JOHN LUBBOCK ON ANTS, BEES, AND WASPS. 287 



In another experiment with Lasius myer I used tlie dark yellow 

 glass, dark violet glass, and a violet solution of 5 per cent, ammouio- 

 sulphate of copper, diluted so as to be, to my eye, of exactly the 

 same tint as the violet glass ; in 8 observations the pupse were three 

 times under the violet solution, and 5 times under the yellow glass. 

 I then removed the yellow glass, and in 10 more observations 

 the pupae were always brought under the solution. 



It is interesting that the glass and the solution should affect 

 the ants so differently, because to my eye the two were almost 

 identical in colour. The glass, however, was more transparent 

 than the solution. 



To see whether there would be the same difference between red 

 glass and red solution as between violet glass and violet solution, I 

 then (Aug. 21) put over a nest oi Formica fusca a red glass and 

 a solution of carmine, as nearly as I could make it of the same 

 tint. In 10 experiments, however, the ants were, generally speak- 

 ing, some under the solution and some under the glass, in, more- 

 over, as nearly as possible equal numbers. 



Aug. 20. — Over a nest oi Formica fusca containing 20 pupae, I 

 placed a saturated solution of bichromate o£ potash, a deep solution 

 of carmine, which let through scarcely any but the red rays, and 

 a white porcelain plate. 



Observation 



1. Under the bichromate of potash were pupae, carmine 18, porcelain 2. 



2. 



4. 



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6. „ » 



7. J] jj 



8. „ )) 

 9' >> )> 



10. 



11. .. » _ _ 



Total 18 81 124 



