=18= 
of 69.3 per cent occurred in the larval collections and in 1921 it 
reached the high figure of 86.1 per cent. Previous to and after those 
vears the mortality fluctuated between 27 per cent and 55 per cent but 
there were no outstanding years. There appears to be a close correla- 
tion between the abnormally high larval mortality caused by 'wilt' and 
the reduction in the gipsy moth population in New England. The last 
year of extremely heavy infestation, 1921, was the critical year in the 
gipsy moth infestation in New England. In 1922, 1923, and 1924 a great 
decrease in the dispar infestation occurred. Since that time the infes— 
tation has never even approached the intensity of 1921. It would there- 
fore appear that one would be justified in concluding that 'wilt' was a 
very important factor in checking the ravages of P. dispar in New Eng- 
and. 
Mortality and parasitism of brown-tail moth.--"The examination of 
larvae from hibernation webs, collected in 29 towns in Maine, New Hamp— 
shire, and Massachusetts, to secure information on mortality and parasi-— 
tism (of the brown-tail moth(Nygmia phaeorrhoea Don.)) has been com- 
pleted by J. A Millar, J. E. R. Holbrook, and C. M. Symonds. Mr. Mil-— 
lar reports that 15.6 per cent of the larvae found in 268 webs were 
dead. Of the larvae dissected 28.3 per cent were parasitized. Examina— 
tion of material from practically the same towns a year ago showed 11.4 
per cent of the larvae dead, and 25.5 per cent of the larvae dissected 
were parasitized." These collections were "made before the time of the 
lowest winter temperatures." 
Bordeaux mixture beneficial addition to arsenicals.—-S. F. Potts, 
Melrose Highlands, in a manuscript just prepared for publication, says 
he found that "when Bordeaux mixture was added to lead arsenate, Paris 
green, and calcium arsenate (respectively) the solubility of the arsenic-— 
als was much reduced and their adherance greatly increased, the increase 
being several fold in the case of Paris green and calcium arsenate." 
Burning=-standing method controls Dendroctonus monticolae Hopk.— 
J. C. Evenden, Coeur d'Alene, Idaho, reports that "During the past sea— 
son an investigation (under the field supervision of L. G. Baumhofer 
and T. T. Terrell) was concluded relative to the effectiveness of the 
burning-—standing method of control as practiced against outbreaks of 
the mountain pine beetle in lodgepole pine. This method consists of 
Spraying an inflammable oil upon standing infested trees and then burn— 
ing. The purpose of this investigation was to determine what per cent 
of the brood was left in the upper portion of the tree which could not 
be reached with the oil. * * * The results of this investigation show 
that in the area examined the straight burning-standing method of con- 
trol destroys approximately 90 per cent of the insect broods, even 
though a larger per cent of the infested bole is left untreated. This 
is explained by the fact that the insect broods are much lighter in 
the upper portion of the bole than at its base." 
