Rau—Longevity in Saturniid Moths. 13 
followed with a like mean of 8.43 days and the Fall River 
lot brought the lowest mean of 7.63 days. 
This divergence invites investigation. Does the cli- 
mate under which the larva lives, or the food supply, or 
the shorter or longer period in the larval stage (due to 
approaching cold or diminishing food supply), do any 
or all of these things affect the adult life? All of the an- 
imals had fed in their native haunts; all had passed 
through.the entire formative period of their lives under 
unrestricted, natural conditions of their own habitat; 
when they came to us they were in the quiescent stage, 
waiting for the warm days of spring to emerge; nour- 
ishment could no longer be a factor in their lives. If the 
St. Louis climate affected the strangers in so marked a 
degree, why were not all affected alike? 
This points to new fields of investigation. Herein lies 
excellent opportunity for ascertaining the causes of 
lengthened or shortened adult life; whether it be a spe- 
cific trait or in how far it is merely the result of individ- 
ual environment; and, if a specific character, whether 
it can be made to vary as such or can be permanently 
altered for the race by artificial conditions. It would be 
well if such work could be done from year to year, at 
localities remote from one another, individual records 
in large numbers accumulated, the place mode found and 
these compared with the climatic and other conditions. 
CALLOSAMIA PROMETHEA, 
In 1911 we obtained notes on the longevity of 170 in- 
sects of this species from the Créve Coeur region, St. 
Louis. Here we found that the unmated males lived 
longer than the mated males, and likewise the unmated 
females exceeded the mated females, and that the fe- 
males, all taken together as a class, lived longer than the 
males. 
In a lot of cocoons of this species received from Fall 
River in 1913, 104 insects emerged between May 19 and 
