BUREAU OF ENTOMOLOGY. 265 



Compsilura concinnata was slightly less abundant than has been 

 tlie case for the past three years, but in some localities it was present 

 in satisfactory numbers. The species is widely distributed, having 

 been recovered during the present summer in the Annapolis Valley 

 in Nova Scotia. It attacks many species of native caterpillars and 

 is particularly valuable on that account. This habit also makes it 

 possible for the species to maintain itself in territory wjiich is not in- 

 fested with the gipsy moth or the brown-tail moth. 



Blepharipa scvtellata has been found more widely distributed this 

 year than heretofore, and in some locations a fair degree of para- 

 sitism has been i^corded. In the territory as a whole it probably 

 has not reached its maximum numbers. Field collections indicate 

 that Apanfeles 7iielano8celU is not quite as abundant as was the case 

 Jast year. This is evidently due to the work of secondary parasites, 

 as many of these have been reared from cocoons of the second genera- 

 tion of Apanteles. This species probably has not increased to 

 maxinuun numbers. 



Cdlosoma sycophanfa was not as abundant this year as heretofore, 

 and this was particularly true in ^ome localities where it had been 

 very numerous during the past two or three years. The wilt disease 

 was not nearly as common as usual and this condition seems to be 

 ratlier universal throughout the territory infested with the gipsy 

 moth. Further studies are being conducted relative to the Japanese 

 disease of the gipsy moth {Streptococcus disparts)^ and more colonies 

 are being liberated in order that a thorough study of its value may be 

 made in the field. 



While the area infested with the brown-tail moth was considerably 

 reduced during the past year, the insect seems to be increasing 

 sliglitly in the eastern part of the territory. Collections of brown- 

 tail moth webs from 100 towns were made during the winter by State 

 and town authorities and forwarded to the laboratory. Dissections 

 of about 10,000 larvae taken from these webs indicate that Apanteles 

 laeteicalor was present in small numbers, while Meteorus versicolor 

 was much less abundant. The most common parasite found in these 

 collections was Zygohothiia nidicola ; 20 per cent of the caterpillars 

 in the entire lot were parasitized by this insect. 



Only a few localities have been found this summer where brown- 

 tail moth caterpillars are at all abundant, and the fungus disease 

 {Empusa aulicae) has not been reported. 



Work on a more effective material for banding trees is under way 

 and preliminary tests to determine the relative value of dusting with 

 arsenate of lead versus spraying have been started. 



The study of the gipsy moth problem on cranberry bogs has been 

 nearly completed and much valuable information secured. 



The work of securing data on the mortality of different species of 

 trees that have been defoliated is being continued and silvicultural 

 investigations are being carried on principally on the sample plots 

 established some years ago. 



Quarantine work. The quarantine of the areas infested with 

 the gipsy moth and the brown-tail moth made necessary during the 

 fiscal year the inspection of 29,394 shipments. These consisted of 

 forest, nursery, and quarry products; also Christmas trees and 

 greens. 



151352*' 19 18 



