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APHIDES. 



The season of 1 898 has witnessed an unusually widespread 

 attack of aphides, or " green flies," as they are commonly 

 called, upon trees, plants, and flowers of many kinds. 

 (Aphides are termed '^green flies" indiscriminately, as if they 

 were of the same species, though each kind of tree, plant, 

 and flower has its peculiar species, with as well-defined 

 distinctions as the host upon which it is found.) It is believed 

 that the mildness of the winter and the absence of sharp 

 frosts preserved the hibernating aphides of species that are 

 generally affected by normal winter weather ; while the 

 abnormally small rainfall also favoured, without doubt, the 

 preservation of these species. 



Among the trees most seriously attacked by aphides were 

 limes and beeches. The foliage of the former trees, in some 

 cases, shone with the honeydew falling from the numbers ot 

 aphides on the under surfaces of the leaves ; their fragrant 

 blossoms were materially lessened by the injurious action 

 of the insects ; and many of the leaves withered and fell 

 prematurely. Varieties of ornamental limes in gardens 

 and shrubberies, such as Tilia argentea, europea^ and eiLchloray 

 suffered particularly from the continuous action of aphides 

 in the past season. The aphis infesting limes is known as 

 Pterocallis tilicBy of the family LachntncB, whose wingless 

 viviparous female is yellowish-green with a black head, 

 and a long and narrow body with black stripes upon the 

 abdomen. The winged female is yellow with dark legs, 

 and ample iridescent wings with forked cubital veins. 



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