536 PROCEEDINGS OF THE ACADEMY OF [Oct., 



An artificially mixed group, now in my possession, was created 

 partially by design and partially by incident, and it curiously 

 illustrates my theme. As mentioned by Dr. W. ^I. Wheeler,''^ 

 Stenamma fulvum piceum sometimes feed their larvae upon pieces of 

 the pupre of Cremastorj aster Uneolata. Desiring to know whether 

 these ants would, when without larvre, themselves devour ihe 

 Cremastogaster pupse, I gave a goodly number of such puppe to 

 each of several groups of Stenaramas living in Petri cells. In 

 every group of Stenammas some portion of the Cremastogaster pupse 

 was adopted and taken care of, at least during several days. In 

 one group only, three of the Cremastogasters were brought to the 

 active stage, and continued to live with the Stenammas and to share 

 their labor of rearing a single introduced male pupa. Probably 

 these three Cremastogaster pup?e were so long in the care of the 

 Stenammas that they were overlaid or smeared with the Stenamma 

 odor before they became animate, and that their inherent odor was 

 therefore obscured. Their own standard of congenial odor would, 

 by earliest impression, be that of the Stenamma group. These 

 Stenammas, which were of the C colony, had previously reared 

 four workers from pupse of the E colony, and I had removed these 

 workers from their cell before the Cremastogaster pupie therein had 

 become active. The four workers had meantime been segregated 

 in another cell. When the Cremastogasters were about twelve 

 days old, I returned the E Stenammas, after an absence of twenty 

 days, to the C Stenamma cell. They were cordially received by, 

 and at once filiated with, their foster C queen and workers, and 

 they made no attack on the previously unknown Cremastogasters. 

 But the little Cremastogasters attacked them frequently, until, in the 

 course of a day or two, experience had shown them the futility of 

 attempts on the life of newcomers so much stronger than them- 

 selves. Cremastogaster Uneolata introduced from outside were killed 

 under attacks from all the ants in this mixed group. 



That there is a relationship between the inherent odor of the an^ 

 and its color, which gradually deepens with age, and that the odor 

 of the queen is stronger than is that of her workers, is shown by 

 the following experiment. I brought a colony from the woods, 

 placed it in its native earth upon a Lubbock nest, and sequestered 



*"" Habits of Ponera and Stigmatorama,'' Biological Bulletin, Vol. 2, 

 No. 2. 



