466 PROCEEDINGS OF THE AMERICAN ACADEMY. 



majors were several times seen drumming on the heads of these two 

 classes, both immediately before this activity took place and during its 

 performance, whereas this drumming was never seen in the other two 

 classes. Apparently the same stimulus is used by ants to make aphids 

 give out secretions (Forel, '74, p. 251) and to make ants regurgitate 

 (1. c, p. 243. See also AVheeler, : OV, p. 438). This leads me to think 

 that it is the ant desiring food, rather than the one giving it, which 

 does this tapping. Secondly, throughout all my observations on this 

 species and C. amej-icanus, it is the class of large ants which has less to 

 do with collecting food than the other classes. Thirdly, the large ants 

 are, on the whole, so much more lazy than the intermediates and 

 minors that it is characteristic for them to take food which is easily 

 obtained from other ants near at hand rather than to seek it or prepare 

 it for themselves. Of course they probably do often obtain other food, 

 and the other classes certainly sometimes receive regurgitated food; 

 but for the reasons stated, I am inclined to think that in general the 

 majors are more apt to receive regurgitated food, the intermediates and 

 minors to give it. On one occasion I saw an intermediate and a queen, 

 on another a minor and a queen engaged in regurgitation, but I am 

 unable to say which way the food went during the process. 



In licking, all three classes took part, but the majors slightly less 

 often. The majors were never licked, and the minors seldom, the inter- 

 mediates being most often the objects of this activity. There were not 

 many individuals, however, which shared in this activity, so that this 

 evidence may not have great weight by itself; it may, however, help 

 to confirm other evidence. 



Practically the same conditions in regard to tending the young hold 

 true here as in the same colonies out of doors, viz. that there are many 

 minors, few intermediates and no majors so engaged. This was par- 

 ticularly noticeable in colony R 18, where the nest consisted of two 

 chambers, an upper and a lower, with a short gallery connecting the 

 two, and another gallery leading to the surface. It was a marked fact 

 that day after day the large and some of the intermediate ants stayed 

 in the lower chamber, while the other intermediates and all the small 

 ants were in the upper chamber with the larvae. Moreover, when the 

 ants were stimulated with the heat from the electric bulb (pp. 440-443), 

 it was nearly always the small ants which carried the larvae toward the 

 heat, or away from it when it was too great. In regard to the chambers 

 and galleries, I have noticed both here and in out-of-door colonies that 

 ants do not, as a rule, collect in the galleries, but use these rather as 

 passages ; they are inclined to huddle together in the chambers. 



In building, both in digging and in carrying earth, it was the majors 



