Vol. X. December, 1905. No. i 



BIOLOGICAL BULLETIN 



THE PROGRESSIVE ODOR OF ANTS. 



ADELE M. FIELDE. 



I. STATEMENT OF HYPOTHESES BASED ON RECENT AND 

 FORMER EXPERIMENTS. 



1. The Specific Odor. The mother-ant transmits to her off- 

 spring the distinctive odor which is identical for ants of all ages 

 and of both sexes within the species. This odor is appreciated 

 among ants by organs near the proximal end of the funicle. 1 



2. Progressive Odor. Female ants, including queens and 

 workers, have, besides their specific odor, an odor which may be 

 termed progressive. Queens of different lineage have different 

 progressive odors. In a queen this odor is either unchanging or 

 changes very slowly, and it is similar to that of her newly- 

 hatched female offspring. 



a. As worker-ants advance in age their progressive odor 

 intensifies or changes to such a degree that they may be said to 

 attain a new odor every two or three months. This progressive 

 odor is appreciated among ants by organs in the penultimate 

 joint of the funicle. 2 



b. Male ants have no progressive odor unless it be super- 

 ficially incurred through association with workers ; but the male 

 carries latent in his spermatozoa the progressive odor of his 

 mother. In other words the progressive odor is always recessive 

 in the male ant. 



c. The progressive odor of each new generation of females is 



1 "Artificial Mixed Nests of Ants," A. M. Fielde, BIOLOGICAL BULLETIN, Vol. 

 V., No. 6, November, 1903, p. 320. 



2 "Farther Study of an Ant," A. M. Fielde, Proceedings of the Academy of 

 +\ 'at nra I Sciences, November, 1901, p. 531. 



