Notes on the first Appearance of the Aphis Lanigera 163 



threatened. He observed, that they are more detrimental 

 to the Crab stocks than to the Apple trees and that they do 

 not attack the Pear. 



Nov. 8, 1790. Visited my Garden at Spring Grove; no 

 insects were there, and Smith, my gardener, had never 

 heard of an insect attacking Apple trees, in the manner 

 above described. 



9. Saw Mr. Aiton at Kew : his Majesty's gardens have 

 not been attacked, and he likewise has not heard of such 

 an insect. 



Called at Mr. Lee's at Hammersmith. He told me that 

 all his young Apple trees were full of insects, and that he 

 was at that moment employing smoke in hopes of destroy- 

 ing them. He first observed them last year, but they were 

 not numerous ; this year he has not a young Apple tree free. 

 He shewed me the insect on the stem of a Pyrus Specta- 

 bilts ; they were near the ground, in detached spots as white 

 as meal. Wherever they were fixed, the bark under them 

 was cankered in a high degree, and was swelled into a hunch 

 above the level of that on the other side of the branch. 



15. Called this day at Kennington, and saw Mr. Michel- 

 son. He had known the insect about three years, but was 

 not certain, exactly, when he first observed it ; believed, if it 

 came from France, that it had been brought with young trees, 

 and not with Apples ; he had never seen it on fruit, though it 

 was abundant on the trees from which the fruit was gathered 

 It did not begin in his nursery, several gardeners had com- 

 plained of it before he did, but he could not recollect their 

 names : had been told, that the insect was very rife at Maid- 

 stone, but did not know how long it had been observed there. 



