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On Two Species of Insects, fyc. 



driven away ; for the leaves of two Pear Trees which grew at some 

 distance were almost wholly destroyed, and the foliage of the Med- 

 lar and Cherry Trees in the vicinity sustained a good deal of injury 

 from them. Nearly all the leaves which contained any of the larva? 

 were collected and burned, and comparatively very few of the larva? 

 escaped ; and I do not at all doubt but that by adopting the same 

 measures next year, T shall succeed in securing my Pears from 

 future injury. 



There is another species of insect which frequently injures the 

 Pear tree, whose depredations are less visible, and consequently 

 less known to gardeners. It has greatly the appearance of an aphis, 

 and is found dispersed over the under surface of the leaves whilst 

 young, and is always immersed in a globule of honey ; in their more 

 mature state these insects are found congregated round the base 

 of the buds, particularly those which are calculated to form blossom 

 buds. In this, as in their first situation, they emit much honey, 

 and the transmutation of the leaf bud into a blossom bud is pre- 

 vented. A large number of humble bees and wasps are always 

 attracted by the honey ejected by this insect, which will never fail 

 to indicate its presence to the gardener. It is in size a little less 

 than the black aphis usually seen upon the Cherry Tree, and its 

 colour, when it is young, is a dull green with dotted lines of pale 

 brown : and in its mature state its colour is dark brown, with trans- 

 verse stripes of green across its back. The colour of the male, 

 which is winged, is nearly black, except the upper part of the 

 abdomen, which is a dull flame colour. It is (as Mr. Curtis in- 

 forms me), the Psylla Pyri of Linnaeus. I noticed it in the garden 

 here about forty years ago, when it rendered all the crop of Pears 

 perfectly worthless. I have subsequently pointed it out to gar- 

 deners in other situations ; and I suspect that it often exists un- 

 noticed, and greatly injures the quality of the Pear. I washed my 

 Pear Trees with an infusion of tobacco in the spring, which appeared 



