LIFE HISTORY OF CARPENTER ANT. 1 99 



able variation in its character, and considerable fluctuation in its 

 amount. 



Relations to Light and Color. 



In endeavoring to work out the relations of these ants to light 

 and color I have resorted to experiments modeled after those 

 made by Fielde, Lubbock and others, on other species of ants. 

 I have, however, used slightly different apparatus from that used 

 by either of these investigators. In the first place I constructed 

 a nest of the Fielde type which was twenty-four inches long and 

 nine and one half inches wide, and which contained a hall-way 

 one and one half inches wide, running longitudinally through the 

 center, with six rooms, each 4 by 4 inches, on either side of the 

 hall-way. The outer walls of the nest were bound by black 

 binding paper and the walls between the rooms were made of 

 two pieces of glass with a strip of black paper between them, so 

 that all the walls of each room were perfectly darkened and no 

 light could enter the rooms except through the glass plates placed 

 over them and through the small pieces of glass tubing which 

 formed the entrances from the hall-way. The nest was connected 

 with a feeding-room by means of a piece of glass tubing which 

 led from one end of the hall-way. The hall-way was covered 

 with a strip of clear glass, and as covers for the rooms I used 

 glass plates of the following descriptions : 



1. A deep red glass which transmitted only the red rays of the 

 spectrum. 



2. A brownish orange glass which transmitted all of the red 

 end of the spectrum including a large part of the green. 



3. A green glass which transmitted all of the green rays and 

 a small part of the red. 



4. A deep blue glass which transmitted all of the blue end of 

 the spectrum, including a very little of the green. 



5. An indigo-blue glass transmitting all colors of the spectrum 

 to some extent, but showing narrow absorption bands in the red 

 and green. 



I also used cells containing carbon disulphide to shut out the 

 ultraviolet rays. 



With this apparatus I performed the following experiments : 



