32 PROTECTION OF PLANTS, 1918-19 



In addition to the artificial control work against the brown-tail moth, natural 

 control forces have been brought to play against this pest by the introduction 

 and colonization of three different species of parasites. These were all reared at 

 the Gipsy Moth Parasite Laboratory, Melrose Highlands, Masssachusetts, through 

 the courtesy of Dr. L. O. Howard and Dr. A. F, Burgess of the United States 

 Bureau of Entomology. The parasite work was continued for four successive 

 summers and during that time over 100,000 specimens were imported into 

 Canada. 



The Braconid, Apanteles lacteicolor Vier, has been recovered in New Bruns- 

 wick and Nova Scotia. The brown-tail webs collected during the winter are 

 saved until spring, and the parasites reared from the larvae as soon as the latter 

 leave their nests. 



The Tachinid, Compsilura concinnata Meig., has been liberated in Quebec, 

 New Brunswick and Nova Scotia. This parasite was recovered at Fredericton in 

 1918, two years after the last colony was liberated. Eighty-six thousand, seven 

 hundred and forty-two native hosts were collected to obtain this recovery, which 

 was made from Hemerocampa leucostigma. The other hosts used were Euva- 

 nessa antiopa, Datana ministra and Pontia rapae. 



The predaceous beetle Colo soma sycophantahas also been liberated in Quebec, 

 New Brunswick and Nova Scotia. This insect can withstand our rigorous 

 climate as several specimens were kept at the Fredericton Laboratory for a number 

 of years. Specimens have been recovered in the field twice, but not within the 

 past two years. This coming summer a field scout will be made in several loca- 

 lities. , 



