THE PROGRESSIVE ODOR OF ANTS. 9 



a newly hatched Cainponotus pictJis male, the offspring of a virgin 

 worker, a brother or cousin of the one in the E nest above 

 mentioned. These ants of the D nest at once began to harry 

 him, and although he was eleven millimeters long and very 

 sturdy, while none of the Stenammas were more than five milli- 

 meters in length, they harried his life out within two days. Repe- 

 titions of this experiment gave similar results in every case. 



The eggs from which these Cainponotus pictns males were 

 produced were deposited by their virgin worker-mothers in May, 

 1905, five months after the said mothers were separated from the 

 Stenammas that the said mothers had lived with during the first 

 five months of their lives. It therefore appears that the male 

 progeny of virgin workers have not the progressive odor which 

 characterized their mothers. The males have, however, a specific 

 odor, an odor recognized by the ants through certain joints of 

 the antennae, and this odor is doubtless the stimulus calling forth 

 the exceeding care given by the workers to young males with 

 whose specific odor they are familiar. 



On August 26 I put into each nest, the E and the D nests 

 above described, two males of Stenamma fnlvnni. These males, 

 the first of their species ever encountered by these workers, wery 

 treated alike in the two nests. They were so eagerly grasped be 

 several residents at once that it seemed as if they must lose their 

 lives through the determined efforts of the workers to retain 

 them. They were not left free for several hours ; but so judi- 

 cious were their virgin captors that no injury was done to the 

 captives, and they lived in health and honor many days in these 

 nests. In the E nest the Camponotns pictns male continued to be 

 their associate. 1 In both the E and the D nests newly hatched 



1 A dealated queen Camoponolus pictus captured alone in the open on July 5, w 

 kept in isolation till August 15, 1905, when she received amicably into her small 

 artificial nest two young males of her species, the offspring of virgin worker ants. 

 She licked them, regurgitated food to them, and during the several days that they 

 remained under my observation, remained in close companionship with them. Later 

 on this queen also received in amiable fashion the virgin mothers of these males, the 

 worker-mothers having been kept by me in segregation during their whole lives. As 

 this queen was captured near the spot in which the workers had their origin a year 

 earlier, these ants may all have been of one colony. This queen killed young males 

 of Formica argentata and Stenamma fitlvum introduced into her nest. 



