468 PROCEEDINGS OF THE AMERICAN ACADEMY. 



(p. 469). Fighting is probably partially represented by " disturbed by 

 knocking." 



2. Observations. — In the out- door work on Camponotus herculeanus 

 pictus it was evident that many more ants, probably even a greater pro- 

 portion of the colony, took part in the various activities than was the 

 case with Camponotus americanus in the laboratory ; and yet, when com- 

 pared with the total population, it was noticeable that few were 

 engaged in any kind of work at one time. This was best seen in 

 foraging ; for no matter how many ants were in the field, when the 

 nest was opened a vastly greater number of individuals was revealed 

 within. 



In regard to those activities which were successfully observed in the 

 field, it was found that the intermediates and minors take a much 

 more active part than do the majors, and on the whole, the intermedi- 

 ates are here slightly more active than the minors. 



Except for those ants which were captured, only two, an intermedi- 

 ate and a major, were seen actually carrying in food. 



The majors were least active in " tending the young," the intermedi- 

 ates more active, and the minors most so. 



As for building, all sizes were seen carr)ang earth, though the two 

 smaller sizes excelled in this, especially the minors. No ants were 

 observed digging, except those which were captured. 



The act of carrying I think is most frequently manifested when the 

 ants are somewhat excited, either by some disturbance or by the pres- 

 ence of food. This activity is on the whole not very common, but in 

 these out-of-door nests, the process seems to be one of actually carry- 

 ing rather than of dragging, which was observed in the Barth nests 

 (p. 467). ^ , ^ 



My impression is very strong that, while all classes are disturbed 

 when the nest is knocked upon or broken into, and while all will attack 

 an intruder vigorously, it is on the whole the majors in this species 

 which exhibit most zest in this response. They gnash their jaws, curl 

 their abdomens forward under the rest of the body in order to throw 

 poison on the enemy, and appear very savage. If they once get hold 

 of an enemy, they cling with bull-dog tenacity, keeping a firm grip 

 with their mandibles even after death. While all this is also true to 

 some extent of the intermediates and the minors, it is the majors which 

 are the fiercest. 



The note-book evidence, then, seems to show that the minors are 

 the most active in tending the young, somewhat larger ants in foraging 

 and in building, and that the majors are more or less reserved for fight- 

 ing. There is, however, no hard and fast division between classes 



