Insects, etc.. Injurious to the Plum. 383 



advised as a late winter wash where aphis is prevalent. Mr. 

 Howard Chapman, of Western Cross Farm, Greenhithe, was the 

 first to point out the great use of this wash as a means of checking 

 the Leaf-curling Plum Dolphin. 



Kefeeenoes. 



(1) BucMoii, G. B. 'A Monograph of British Aphides,' vol. II., p. 64 (1877). 



(2) Theobald, F. V. Second Report on Economic Zoology (Brit. Mus. N.H.), 



p. 148 (1904). 



(3) Theobald, F. V. Eeport on Economic Zoology for the year ending 



April 1st, 1907, p. 74 (1907). 



(4) Whitehead, Sir 0. ' Insects Injurious to Fruit Crops,' p. 88 (1886). 



(5) Ormerod, B. A. ' Handbook of Insects Injurious to Orchard and Bush 



Fruits,' p. 146 (1898). 



THE MEALY PLUM APHIS. 



{HycdoiDterus pnmi. Fab.) 



The Mealy Plum Aphis is never very obnoxious in Kent, but 

 in Worcestershire it is very abundant. It also causes some annoyance 

 in Herefordshire, and is recorded once from north Devon. 



I have frequently seen it in Surrey and Middlesex, especially in 

 the neighbourhood of London. Carpenter (4) records it from Navan, 

 Ireland. 



This aphis is quite distinct from the previous species and does 

 not seem to do so much harm directly to the trees, for leaves keep 

 green and sound when laden with these insects for some time. The 

 great quantity of honeydew they secrete falls on to the leaves below, 

 and on to the fruit, and thus its obnoxious nature manifests itself. 

 I have seen good crops of plums spoiled by it. 



LiFE-HlSTOEY. 



The Mealy Aphis appears in June and July, usually the latter 

 part of July, but in 1906 they made their appearance early in the 

 month. In 1905 they appeared early in June at Wye, and Mr. 

 Getting recorded them in large numbers at the end of June in the 

 same year at Eoss. They continue increasing under the leaves until 

 the end of August, and into September. During 1907 I received a 

 communication concerning the ravages of this aphis from Scotland, 

 and on the 20th of November numbers were sent on late plum leaves. 



They are easily told by their pale green colour, and the dense 

 mealy secretion they become covered with. The honeydew falling 



