GALL MITE. 215 



figured at p. 212, magnified), much produced and lobed at one 

 end, in a way that would correspond with the caudal extremity 

 of the contained Acarus. The pellicle was similarly trans- 

 versely striated, and, before the exclusion of the contained 

 Gall Mite, was dragged out of all resemblance to the form of 

 an egg, and left sometimes with the markings at the two 

 extremities, having much the appearance of a cast skin, 

 except in the absence of limbs and appendages. 



Later on in 1877 I continued the search, and found at the 

 beginning of August what I took to be an earlier form of the 

 egg. In this case the egg was of a perfectly regular oval 

 shape, larger at one end than the other, and without strite ; 

 sometimes also slightly produced at the extremities as from 

 pressure of the contained creature, and sometimes also when 

 the time of hatching was at hand these eggs were to be found 

 as before, with the pellicle striated, the shape completely 

 irregular, and the Pliytoptus in the act of exclusion. 



Towards the end of August eggs were still to be found of a 

 regular obtuse oval until driven out of shape by the living 

 tenant. 



Peevention and Eemedies. — Witches' Brooms should be 

 cut off and burnt, and in cases where the tree is much 

 infested with the small gradually-forming tufts of diseased 

 growth it is desirable to cut it down and burn the mite- 

 infested twigs. The Gall Mites have no power of flying, but 

 the wind wafts them about on leaves or broken twigs, or birds 

 carry them in their plumage, and when once well established 

 the attack spreads regularly onwards slowly but steadily to 

 the neighbouring Birches. 



During the last few years Gall Mite attack to the leaf and 

 flower buds of Black Currants has increased to a very 

 serious extent, so as to cause great loss to fruit-growers. 

 This is referred to under its own heading, but as (from their 

 excessive minuteness) there is great difficulty in ascertaining 

 whether there is specific difl'erence in Phijtopti infesting 

 different kinds of plants, the above notes may be of some use 

 as to the general character of the infestation. 



