86 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



Another da}^ was spent in the Annapolis Valley in Nova Scotia. 

 During this trip, I did not see a brown-tail moth web, although a great 

 many susceptible trees were hastily examined. This indicates that 

 good work had been done by the field men. It also indicates the dif- 

 ference in condition of infestations in that territory from what is found 

 in some of the New England States. 



Dr. Hewitt mentioned a series of experiments that are being car- 

 ried on by his assistants to determine the relation of temperature to 

 the successful hibernation of brown-tail caterpillars. Last winter, 

 particularly in the northern part of the infested territory in New Eng- 

 land, large numbers of the brown-tail moth caterpillars died in the 

 webs. Although we do not know accurately the exact causes, we be- 

 lieve that temperature and humidity were very important factors. 



For several years, some experimental work of this sort has been 

 carried on by the Bureau of Entomology and by some of the states, 

 particularly New Hampshire, and some general conclusions have been 

 reached in regard to the effect of temperature on hibernation. The dif- 

 ficulty is the impossibility of securing accurate temperature records 

 so as to determine the degree of temperature which will cause winter 

 killing and whether fluctuations are important in this respect. 



We have come to the conclusion in our work that it is necessary to 

 have a continuous temperature and humidity record at the locations 

 where periodical collections are made during the T\dnter. Experiments 

 are being conducted this yesir along this line, stations having been 

 secured at approximately sea level and at an altitude of about one 

 thousand feet. Continuous records are being taken at these stations 

 and collections of webs secured periodically and examined to deter- 

 mine the condition of the caterpillars. 



Hearty cooperation has existed between the Bureau of Entomology 

 and the Dominion Entomologist in connection with the introduction 

 of parasites into New Brunswick and Nova Scotia. In cases where 

 the parasites of the gipsy moth and the brown-tail moth attack more 

 than one host, it is possible to attempt a colonization of the parasites 

 before these pests become established. This work, however, is largely 

 experimental. 



We have cooperated during the past summer with Professor W^eb- 

 ster, who has charge of the Cereal and Forage Crop Insect Investiga- 

 tions for the Bureau of Entomology. He supplied a man during the 

 summer to make collections and we have rendered such assistance as 

 was possible in securing Compsilura and Calosoma for shipment to 

 New Mexico in order to test the value of these species as an enemy of 

 the range caterpillar. 



We have colonized parasites in all the New England States this 



