1913 E^NTOMOLOGICAL SOCIETY. 57 



PROGEESS OF THE IXTEODUCTIOX OF THE INSECT ENEMIES OF 



THE BEOWN-TAIL MOTH, EUPROCTIS CHRYSOBRHOEA 



LINN. INTO NEW BEUNSWICK AND SOME 



BIOLOGICAL NOTES ON THE HOST. 



J. D. TOTHILL, DlVISIOX OF EXTOiEOLOGY, OTTAWA. 



During the season just closed a beginning was made at the suggestion of and 

 under the general supervision of the Dominion Entomologist, Dr. C. Gordon Hewitt, 

 in the introduction into New Brunswick of the insect enemies of the Brown-tail 

 Moth. Owing to the fact that the host insect is at the present time exceedingly 

 scarce in the Province, attention has been necessarily confined to the introduction 

 of facultative rather than obligate species. Of these facultative species, special 

 eifort has been made to introduce two spcies both of which are native to Europe 

 and both of which have become established, through the efforts of Dr. L. 0. Howard, 

 Chief of the United States Bureau of Entomology, and his assistants, in Massa- 

 chusetts. Each of these species has abundantly proven its practical worth in 

 Massachusetts as a valuable factor in the natural control of both the Brown-tail and 

 Gipsy Moths. 



These insects are respectively the Tachinid parasite Compsilura concinnata 

 Meig, and the predatious ground beetle Calosoina sycophania Linn. 



In order to secure a supply of the Tachinid fly, a journey was made by the 

 writer to Boston during the first week of July. This resulted in the collection of 

 12,000 caterpillars of the Gipsy Moth from points in Massachusetts where the 

 parasite was known to be plentiful. These caterpillars were placed in Fiske trays 

 and through the kindness of Mr. A. F. Burgess were given quarters at the Gipsy 

 Moth Parasite Laboratory at Melrose Highlands. Within ten days' time the very 

 satisfactory total of 2,395 puparia of Compsilura was obtained from the trays; 

 these were picked out of the trays from time to time and sent by mail to 

 Fredericton. 



The shipments arrived at Fredericton in excellent condition, and there were 

 sufficient puparia for the establishment of two strong colonies. Suitable localities 

 were found near St. Stephen and Fredericton respectively, and consequently these 

 two places served as the liherating points for the parasites. After the time for 

 the issuance of the adult flies had expired the puparia were examined, and it was 

 found that about 75 per cent, had successfully given the adult; this gives a total 

 of about 850 adult flies for each colony. 



In the ease of the Fredericton colony an oibservation was made demonstrating 

 the fact that this Tachinid is a strong flyer and is capable of rapid dispersion. 

 At a point three miles from the point of lil>eration as the crow flies, some cater- 

 pillars of Hijpliantria cunea were collected and subsequently dissected; these were 

 found to contain first stage maggots of Compsilura so easily recognized in this 

 stage hy the presence of anal hooklets and by the feeding locality. The observation 

 is of special interest in that the female fly responsible for the three maggots had, 

 in order to find the particular caterpillars, to cross the Elver Si. John, which at the 

 place is almost three-quarters of a mile wide. Thus' a fertilised female fly of 

 Compsilura is capable of flying three miles, including a body of water, almost three- 

 quarters of a mile wide before the completion of larviposition. 



In regard to the predaceous ground beetle Calosoma, a single shipment was 

 received on June 11, through the kindness of Dr. L. 0. Howard, and Mr. A. F. 



