INSECTS 



there the females give birth to a generation of wingless 

 sexual females (B), which, when mature, mate with the 

 males and produce the winter eggs. 



The third of the aphid species that infest the spring 

 buds of the apple is known as the apple-grain aphis, so 

 called because, being a migratory species like the rosy 



Fig. ioo. The winged male (A) and the wingless sexual female (B) of the 

 rosy apple aphis 



aphis, it spends the summer upon the leaves of grains 

 and grasses. The eggs of the apple-grain aphis are usually 

 the first to hatch in the spring, and the young aphids of 

 this species (Fig. 95 A) are distinguished by their very 

 dark green color, which gives them a blackish appear- 

 ance when massed upon the buds. Later they spread 

 to the older leaves and to the petals of the apple blossoms, 

 but on the whole their damage to the apple trees is less 

 than that of either of the other two species. The summer 

 history of the apple-grain aphids is similar to that of the 

 rosy aphis, excepting that they make their summer home 

 on grains and grasses instead of on plantains. In the 

 fall, the winged female migrants (Plate 4) come back to 

 the apple and there give birth to wingless sexual females, 

 which are later sought out by the winged males. 



It would be impossible here even to enumerate the 



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