PARASITISM OF GIPSY MOTH IN AMERICA. 



141 



Undetermined Tachinids. 



Dr. S. W. Williston, in reporting upon a collection of Diptera reared 

 from the gipsy moth in Massachusetts and sent to him in 1891 by 

 Dr. Fernald, stated that there were present two species of Exorista 

 and four of Phorocera. Unfortunately these specimens appear to 

 have been lost before being definitely determined. No such variety 

 of tachinids has been reared from this host in Massachusetts during 

 recent years, but several species as yet undetermined, or represented 

 only by unfamiliar puparia, are in our collection. 



SUMMARY OF REARING WORK CARRIED ON AT THE LABORATORY IN 



1910. 



In Tables IV and V are the condensed results of a part of an 

 extensive series of rearing experiments primarily instituted for the 

 purpose of determining the present status of the introduced parasites 

 of the gipsy moth in America in 1910. They also serve excellently 

 as an indication of the effectiveness of parasitism by native species. 

 In this respect they are typical of the results secured from similar 

 work in previous years. 



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

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





Localities. 



Num- 

 ber of 

 dispar. 

 pupae. 



Moths reared. 



Parasites reared. 





Labo- 

 ratory 

 No. 



Male. 



Female. 



Blepha- 

 ripa scu- 

 tulata. 



The- 



ronia 

 fulves- 

 cens. 



Comp- 

 silura 



concin- 

 nata. 



Miscel- 

 laneous 

 tachi- 

 nids. 



Scarco- 

 phagid 

 puparia. 



2185 



North Andover. . . 



2,700 



500 



1,800 



1,400 



1,000 



800 



1106 



300 



300 



282 



100 



1,050 



1,700 



1,047 



1,000 



1,000 



1,250 



580 



1,700 



500 



400 



1,700 



600 



300 



1,000 



1,100 



900 



500 



500 



1,100 



1,222 



185 



683 



482 



412 



126 



4 



159 



106 



69 



67 



274 



312 



379 



81 



147 



253 



232 



442 



261 



152 



354 



82 



85 



143 



118 



198 



229 



81 



193 



259 



159 



299 



461 



250 



217 



38 



68 



92 



115 



22 



172 



211 



127 



144 



78 



209 



102 



218 



125 



133 



346 



87 



49 



461 



323 



215 



102 



104 



156 



2 

 1 



2 











2186 











2187 



North Andover. . . 

 Stoneham 



3 

 5 

 2 







2 



2188 



1 

 2 







2189 







3 



2190 



Wakefield 



do 







1 



2190A 



1 





112 







2191 



Swampscott 



North Andover. . . 

 Woburn 









2192A 













2192b 





1 









2192C 



North Andover. . . 

 Saugus 











2193 







2 





1 



2194 



Melrose 2 



1 







1 



2196 



Stoneham 



Beverly 











2197 











13 



2199 



. do 





2 

 2 

 1 



17 

 1 







5 



2280 







1 



31 



10 



2281 



North Andover. . . 

 do 







2282 



8 





41 



6 



2283 



Beverly 







2284 



do 











2285 



Gloucester 





3 





52 



5 



2286 







1 



2287 



do 













2289 



North Andover. . . 

 do 





1 

 3 

 4 









2290 









1 



2291 



do 









2 



2293 













2294 



do 





2 







2 



2295 



Middleton 



Total 

























27, 215 



7,531 



5,342 



15 



47 



18 



4 



53 



1 Prepupae. 



2 Partly from another locality. 



' Tachina-like species, puparium. 



4 Exorista blanda. 



e One tachina-likeand one unknown native species, 

 puparia. 



