Insects, etc., Injurious tcj Currants. 



231 



THE CURRANT GALL MITE. 



( Ei'idpli lies rihis. >(;ilepii. ) 



The disease caused liy this mite is popuhirly called " Big iUid." 



During recent 3'ears the mite has liecome one of the worst pests 

 with whieh the friiit-grower has to reckon, the damage done is 

 enormous, and no nreans ot extermination has yet Ijcen found. 



The difficulty experienced in getting rid of the disease is due 

 entirely to the position of 

 the mites inside the Ijuds. 

 Although, thanks to the 

 work of Xewstead (f), 

 Lewis (2), and Warbnr- 

 ton (o), we know a great 

 deal about the life-history, 

 yet there are still nuiny 

 points upon which we have 

 not yet sufficient knowdedge. 

 The minute mite that causes 

 the disease belongs to a 

 family of acari now Ixuowii 

 as the ]'Ji-ioiih iiii'](i\ formerly 

 as riiiiii>i>l'iihf. 



Other mites whicli be- 

 long til this family are pro- 

 tected fiy tlie bud in a 

 similar way : the Xut find 

 Mite {E. lici'lhinii', Anierk), 

 the Birch Mite, E. raiUs 

 (sub. sp. tiiii'iriis) (Can.) and 

 the Yew Mite {E. hi,;, 

 Murray), all of which cause 

 the buds to swell in the 



same way as does E. rihis on the black curraut. Galls arc formed 

 by many of these miles on tlie leaves of various plants aud trees, 

 such, for instance, as the several kinds of small red galls frequently 

 found in nuudjers on tlie leaves of the maple and sycamore, and the 

 common " nail galls " of the lime. 



They are usually situated on the upper surfaces of the leaves, the 

 aperture being fielow, and they may lie covered inside with a whitish 

 downy substance, ilites tielonging to this lamily attack other fruit 



Fin. 17:-,.— BLAPIC rUKI;.VN'T SIhiOTS, Iirilj-IT .VTTAL'KEIJ BY 

 l:rii MITE^, l.KFT XnKM.U.. 



