Insects, etc., Injurious to the Gooseberry. 271 



This fourth brood is unusual, but three frequently occur. Al- 

 though these generations are quite distinct they generally overlap 

 one another. The number of generations appears to depend on the 

 weather. When it turns cold and wet, not only is development 

 arrested but the larvae are actually destroyed ; in warm fine weather 

 they, on the other hand, develop rapidly. 



NATUBAL ENEMIES. 



There are quite a number of parasites recorded on this insect, 

 but on no occasion have I been fortunate in observing any one of 

 them. 



Cameron (5) records the following parasites : Cliptcs nitidula> F. ; 

 Ornalus armalus, Dbm. ; Limncria argcntata, Gr. ; Mesokms mdano- 



[F. Edenden. 



FIG. 139. MALE AND FEMALE GOOSEBERRY SAWFLIES. 



(Natural size and magnified.) 



leucus, Gr. ; M. armillatorius, Gr. ; MesocJiorus confnsus, Hmgr. ; M. 

 grossularicv, Etz. ; Tryplwn ambiyuus, Gr. ; T. bipunctatus, Gr. ; T. 

 ceplialotcs, Gr. ; T. compressus, Etz.; Cteniscus friyidiis ; Peril i**n* 

 limitarix, Gr. ; PolysplLincta ribesii, Etz. ; Pyyostolus stricticus, Fab. ; 

 and Dcyecria flavicans, Gour., in Europe. 



Dr. Asa Fitch (6) has bred in America a Chalcid fly, the Tricho- 

 gramma prctiosa of Eiley, from the eggs of this Nematus, as well 

 as from the ova of Aleyrodes and from those of a Noctuid moth. 



The parasitised eggs of the sawfly become brown and abnormal 

 n shape. The female Chalcid takes two and a half minutes to lay 



