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The Monthly Letter for July referred to parasitism of the orien-— 
tal moth (Cnidocampa flavescens Walk.) by the tachinid Chaetexorista 
javana B.&.B. at points in Boston and vicinity, where the parasite was 
colonized in 1929 and 1930. The records are now complete and R. C. Brown 
reports that "the average percentage of parasitism for all points was 
8.99, based on 1,904 collected cocoons. The percentages of parasitism 
for the different points ranged from.2.42 to 28.44." 
J. E. R. Holbrook, Melrose Highlands, Mass., has completed a sum— 
mary of experiments to determine the number of larvae and pupae of the 
gipsy moth that a single larva of Calosoma sycophanta L. would destroy 
during its existence. "This experiment was started on June 26 and ended 
July 27 * * * One beetle larva was confined in each of the trays, which 
were kept stocked with at least 10 specimens of P. dispar. As the spec— 
imens died or were eaten, replacements were made with living stock. * * * 
In 18 cases where the beetle larvae developed successfully to the succeed— 
ing stage, a total of 305 P. dispar individuals were eaten; the average 
being 16.94, or the figure 17 for practical purposes. The total of 305 
P. dispar included 51 fifth-stage, 62 sixth-stage larvae, and 122 male 
and 70 female pupae * * * It appears that a more reliable method for ob- 
taining feeding data would be from a system where weights of the larvae 
and pupae are considered, due to the lack of uniformity of specimens and 
the inability of determining, except superficially, the quantity of edi-— 
ble material which remains after the victim has been abandoned." 
W. D. Bedard, Coeur d'Alene, Idaho, who has been studying the 
biology of the mountain pine beetle, states: "Sex studies of the moun— 
tain pine beetle show that in newly attacked trees the percentage of at— 
tacking beetles is 59.73 per cent of females and 40.27 percentof males. 
In comparison with this figure, the brood as it emerges from the old 
trees, just prior to attack, was found to contain 50.4 per cent females 
to 49.6 per cent males." 
F. P. Keen, Portland, Oreg., reports that in the Crater Lake 
National Park "fully 50 per cent of the lodgepole stands in areas where 
control work has been done (against the mountain pine beetle) have been 
saved through the work." 
Observations on activities of the hemlock looper in southwestern 
Washington during the latter part of August are reported by Mr. Keen, 
as follows: "The dusting work (by airplane) thinned the number of loopers 
sufficiently to prevent complete defoliation of the trees on some 2,000 
acres and hence saved a very considerable amount of timber from destruc— 
tion this year. Feeding reached a peak about the 15th of August when the 
first pupae were observed. Since that time pupation has increased rapid- 
ly and feeding decreased. Maximum pupation occurred about the end of the 
month. A large area south of the Naselle River presented such insuper— 
able difficulties for airplane dusting that much of it had to be abandoned 
altogether and other portions received an inadequate dosage. 
* * * The area of forest killed through complete defoliation more than 
doubled in extent, while north of the river in the more heavily dusted 
areas very little spread took place." 
