am A ULT—TRICIIOaiiAMMA PRETIOSA RILEY 
S3 
Ii)071 
"^rhe Iciifjth of tlio life eycle was first recorded 1)V Iluhhard (Howard, 1S;>2) in 
ISSSas heiiie 7 days, the host bein^ Ahihama inriilldrca lliil)ner. 
IIlUERNATION. 
Very little is known in ref^ard to the mode of hibernation of inanv of the smaller 
parasitic hymeno|)tera, especially the more minute cfig-parasites, and for this reason 
the following account will be of interest. 
About two years before these observations were made, the method of hibernation 
of this species of Trichogramma was stated by W. A. Honeher who.se account has not 
been accessible. However, Froggatt (I'.tOti) quotes Air. Boucher as follows: 
“ . . . .As the parasite remains dormant in the egg of the Codling Moth’ during the 
winter and sjn’ing motiths, it is evident that the number of parasites that will again 
be pre.sent at the commencement of each fruit .season to continue the de.struction of 
the Codling Aloth’s eggs will depend upon the number of ])arasitized eggs that remain 
uninjured during the winter, the jirojiortion of which, under ordinary circnmstances, 
and without artificial assistance, will be very small ; ” 
Air. Boucher apparently gives no evidence to show upon what his as.sertion is 
based and hence it needs confirmation. The following ilata obtained in the latter 
part of 1904 seems to indicate that his view is correct. 
As shown in table H, the length of the life cycle increased ra]>idly in the fall 
from 8 days in late Se])tember to from 13 to 19 days in < Ictober, uj) to 27 days by the 
second week in Xovember. In fact, the la.st oreighteenth generation varied unusually 
from 19 to 27 days, and the records show that this generation was a small or scattering 
one, the la.st ])rinci])al generation Ireing the .seventeenth (adult about October 11). 
After about this date it is ladieved that hibernation c-ommenced, though adults con- 
tinued to be ])resent, in rapidly decreasing nund)crs, fora month later (to November 
19). In about the mi<ldle of ( Ictober, and later, ])arasitized ho.sts in (he field (includ- 
ing also Alahmna aniilhirrn Hiibner) on corn and cotton were tagg('d and wjitched 
for emergence of the adtdts. Alanv of these were on dried and withered leaves when 
tagged, and when last examined after heavy killing frosts on Xovember 2()th, were 
found on the.se shriveled leaves, which W('rc either hanging to (lu> plants or were on 
the ground. Some of the parasitized hosts, however, had been washed from the 
leaves to the ground by the rain. 'Phe results are shown in the attached tables. 
