Rau—Longevity in Saturnnd Moths. 43 
the proportion for all Saturniids observed in the first 
period, 1909-11, was 116 males to 100 females, while the 
records for 1912-13 show a proportion of 108 males to 
100 females. | 
True Priority of MALE EMERGENCE. 
In a study of the duration of life from the standpoint 
of efficiency for the perpetuation of the species, the fact 
that in practically all of our Saturniid material the males 
emerged from 1 to 5 days in advance of the females is a 
point worthy of thoughtful consideration. Here is the 
average priority! of the males of each population over 
the females: 
TABLE 26. 
Callosamia ee Fall pes pena ere male priority, 3.07 days. 
Philosamia cynthia, New York.......... es male priority, 2.64 days. 
Philosamia south: Phadnis erg ree ee male priority, 1.09 days. 
Samia cecropia, New York ...........-+.+.-+- male priority, 3.47 days. 
Samia cecropia, St. eae Pee erhn Watchin’ Alle 2 Weep male priority, 4.98 days. 
Samia cecropia, St. Louis, River des Péres....male priority, 2.56 days. 
Samia cecropia, South St. Biwcpateri so oi male priority, 1.84 days 
Telea polyphemus, Augusta, Ga. ..........--- male priority, .23 days 
Telea polyphemus, St. Louis .............++- male priority, 1.48 days 
Telea polyphemus, Fall gies eee RT EET Pe female priority, 3.12 days. 
These means give us a concise index to the actual con- 
dition occurring for the whole lot. For the details of 
the rate of emergence throughout the season, and the 
proportion of the sexes for each day, we present the data 
in the following curves. (See Pls. I-V.) For making 
these curves, the two groups of Cynthias, from Phila- 
delphia and New York, were thrown into one lot, sinee, 
if plotted singly, the numbers were too small and too scat- 
tered upon the field to show the evidence clearly. For 
the same reason the Cecropias from the fluffy cocoons 
were combined with the rest of their lot, the River des 
11 The mean date of emergence of males and females was found, and 
this is the difference between the two. 
