The Scale Insects 



object, as indicated in the accompanying figure, and the adult 

 male, which makes its appearance at the time when the females 

 are almost ready for oviposition, is shown at Figure 151. There 

 is but one annual generation in the northern states, and, owing to 

 this fact, the leaves are not attacked, for if the insect were to go 

 on the leaves it would be lost when they fall in the autumn. 

 Upon the fruit it is almost equally rare, although occasionally a 

 specimen is found in such a location. In the south, however, 

 the insect is two-brooded, and the adults of the first generation 

 are found upon the fruit and leaves without danger to the 

 perpetuation of the species, since their offspring crawl back to 

 the permanent portions of the plant before autumn. As a matter 

 of fact, however, even in the south the insect is very seldom seen 

 upon either the leaves or the fruit. 



The insect is subject to the attacks of many natural enemies 

 in the course of its growth. The little ladybirds, as the beetles of 

 the family Coccinellidse are termed, both as larvae and adults 

 feed upon these and other scales. There are five distinct species 

 of chalcidid parasites which lay their eggs in the maturing bark- 

 lice, and while the lice are young and before they have formed a 

 protective scale they are avidly destroyed by the larvae of 

 the syrphus flies, of the lace-winged flies, and by certain 

 small predatory bugs. The most efficient of their natural 

 enemies, however, are probably the ladybirds, since the writer 

 has determined that the internal chalcidid parasites rarely destroy 

 all of the eggs in the over-wintering scales. A large number of 

 scales were examined in the late winter and early spring of 1894, 

 with the result that when parasites were found from two to 

 eighteen eggs were found to have escaped destruction, the 

 average number of eggs in uninfested scales being from sixty-five 

 to seventy-five. In two cases, where a parasite had issued late in 

 the fall (and the small round hole of issuing is readily perceived 

 in the scale), eleven and five eggs, respectively, were found. The 

 ladybird, however, eats everything. 



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