142 



PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 



Table IV includes the results of rearing work in which caterpil- 

 lars collected in the open were used. A large proportion of the 

 collections, probably half or more, was from localities in which 

 Compsilura concinnata is not as yet established, although it will 

 probably have extended its range to include these by the end of 

 another year. It will be observed, however, that the number of the 

 Compsilura reared is very far in excess of that of any native tachinid 

 or other parasites attacking this caterpillar as a host. This is espe- 

 cially encouraging in view of the fact that one year ago less than 

 one one-hundredth of the proportionate number of Compsilura were 

 reared under similar circumstances, and only from material collected 

 over a much more restricted area. 



Table V. — Results of rearing work in 1910 to determine progress of imported parasites 

 and prevalence of parasitism by native parasites of gipsy-moth caterpillars. 



6 



b 



o 



1 



o 



-9 



h3 



Localities. 



1 

 e 



o 

 o 



,Q 



8 

 a 



83 

 ft 



3 

 ft 



•6 



°% 



<z> 



rO ■ 



a 



3 



Number 

 of moths 

 reared. 



Number of parasites reared. 



3 



Is 



s 



CD 



2 <s 



3 08 



'35 3 



O o 



C3 



C3 

 co c3 



O c3 



CO 



© . 

 _ co 



< 



— to 

 O 



"SI 



ft.2 



fl 



pq w 



4317 



Wellesley 



Stoneham 



Wellesley 



do 



1,029 

 535 



2,110 



3,000 



2,000 

 800 



1,250 

 600 



2,000 

 300 

 100 



1,500 

 125 



no 



1,000 

 1,125 

 500 

 230 

 400 

 1,000 

 250 

 800 



150 

 150 

 425 

 300 

 100 

 53 

 341 



158 



298 



716 



962 



599 



300 



846 



308 



902 



234 



54 



566 



69 



14 



818 



934 



207 



56 



20 



338 



61 



286 



103 

 65 



181 



191 



37 



6 



281 



15 



43 



419 



371 



59 



20 



234 



124 



363 



18 



5 



30 



7 



1 



245 



150 



11 



4 



1 



29 



4 



21 



11 

 9 

 29 



18 

 2 



13 



81 



69 

 115 

 177 



88 

 245 

 144 

 317 

 202 



34 

 199 



25 



6 



344 



301 



125 



30 



5 



139 



22 

 106 



43 



11 

 114 

 128 



22 

 4 



42 















4330 



9 



108" 



73 



i* 



6' 













4332 



8 

 4 











4333 











4334 



Stoneham 



do 











4337 













4340 



Wellesley 



Swampscott 



Wellesley 



3 











4341 











4349 



6 





21 







4351A 







4351b 



Winchester 













4352 



6 



2 



12 



59" 













4353 



Wilmington 



Winchester 



Wellesley 



..do 













4354 



""2 

 1 

 1 



1 









4356 

 4359 



23 



38 



34 





4360 



Stoneham (?) 







1 



4362 



1 









4366 



Lexington 



2 



15 

 5 



14 



21 











4367 













4369 



Marblehead 













4370 









31 





4372 



Stoneham- 



Woburn 



Wellesley 











4373 









31 





4377 



1 

 1 

 1 

 1 











4378 



Winthrop 



Burlington 



Lexington 



Manchester 



Total 













4386 













4387 













4392 





























22, 283 



9,610 







337 



25 



2 



4 



14 



1 











1 The identity of this tachinid, the puparia of which resemble those of tachina, but which hibernates as a 

 pupa, is wholly unknown. The adult has never been reared. 



2 From near site of colony of 1910. Recovery of no significance. Masses of cocoons counted. 



3 A few pupae included in this collection. 



In Table V are included results of rearing work in which collections 

 of gipsy-moth pupa3 were used. These were largely made in local- 

 ities near the center of colonization of Blepliaripa scutellata of the 

 same year. The number of Blepharipa secured is higher in propor- 



