1007] 
GIRAULT—TRICIIOnRAMMA PRETIOSA RILFA’ 
85 
The tallies serve to make clear tlie fact that at least as early as Oetolier 12th, 
hiheriiation had eoiiuneneed, hut that by < tctoher 2l)th oulv 2S.5 |)ereeiit were in 
that state, the reinainini; eventually eiiu'rijiui; as adults. After < letoher 2l)th, how- 
ever, table 1\' shows that nearly SO per cent of the parasites had not eiuerijed u]i to 
the time of killiui; frosts (Nov. 20th and a few days earlier), or were hibernating, 
d'he data is not as eonelusive as desirable, for it may be urged that the ob.servations 
were not continued late enough to state definitely whether or not the adults issued 
after November 20th, and then hibernated. Hut as evidence against this, I otter the 
fact that adults failed to i.ssue from 10 fif the.se tagged hosts up to the middle of 
December, they having been carried to \Yashington, D. (’., in vials and couliued in 
the laboratory. 
Another fact indicating hibernation as a larva in the host, is that no material 
increase in length of life could be noticed in the adults in the late jiart of (letoher 
and in November. In reality, they .seemed to perish more easily at that time than in 
the summer. During the ob.servations, mo.st of the adults issued during warm sjiells. 
Incre.\se in Numbers During a Sea.son. 
Assuming that the average number of eggs deposited by a female is 30, a con- 
■servative e.stimate, and that at lea.st half of these will jiroduce other females, the 
jirogeny of a single pair for such a season as 1004 in Texas would total to the un- 
thinkable number of 3, 031, 721, 2(i(), 073, 800, 781 , 2.50, as showTi iu the accompany- 
ing talile by generations. 
