372 SIE J. LTTBBOCK ON ANTS, BEES, AND "WASPS. 



placing the bisulphide over the violet glass was that the ants did 

 not care much whether they were under the violet glass or under 

 the bichromate of potash. 



I now took the same solution of carmine which I had already 

 used. 



10. The ants were under the carmine. 



10.15 „ „ 



10.30 „ most under the carmine, but some under the 



violet. 

 10.45 „ under the carmine. 



11 ,, most under the carmine, but some under the 



violet. 

 Here, then, again the bisulphide made a distinct difference, 

 though not so much so as with the bichromate of potash. 

 I now took the solution of chlorate of copper already used. 



1. About half the ants were under each. 



1.30. The greater number were under the violet glass and 

 bisulphide. 



2. ditto ditto ditto. 

 2.30. ditto ditto ditto. 



3. Almost all were under the violet glass and bisulphide. 

 Here, then, the addition of the bisulphide caused the violet 



glass to be distinctly preferred to the chlorate of copper. 



I then took a solution of sulphate of nickel, almost exactly the 

 same tint, or a shade paler than, the chlorate of copper. 



At 3.45 the ants were under the violet glass and bisulphide. 



4 ditto ditto ditto. 



5 ditto ditto ditto. 

 Oct 18. 



7 a.m. ditto ditto ditto. 



8. About half of the ants were under each. 

 Here the same result was even more marked. 

 I then took some saffron 1 inch in thickness and of a deep- 

 yellow colour. 



12.45. The ants were about half under each. 



1. Most of the ants were under the violet glass and bi- 



sulphide. 

 1.15. ditto ditto ditto. 



2. Most of the ants were under the saffron. 

 Here, again, we have the same result. 



I then tried the different-coloured glasses, all of which, as I had 



