STATE HORTICULTURAL SOCIETY, 91 



than mar the beauty, without seriously damaging the value of the crop, it 

 is impossible to state very definitely the number of species which should 

 be admitted into this category. If we take as our guide in this matter 

 those species which the writers upon noxious insects have thought proper 

 to admit into their works, we may state the number of injurious species, 

 in this country, to be about five hundred ; and from these, one hundred 

 might be selected, which would include all those species which can be 

 said to be seriously injurious, either to the fi\rmer or to the horticul- 

 turist. 



When we come to examine these hundred species in detail, we find 

 that they can be usefully divided into three classes, which we may desig- 

 nate as first class, second class, and third class noxious insects, according 

 to the extent and severity of their depredations. All injurious insects out- 

 side of the hundred might be thrown together as a fourth class. 



I admit into the first class of noxious insects only those species which 

 are so destructive and so generally diffused that, if left to themselves, they 

 would wholly, or at least in great part, prevent the raising of those fruits 

 or other crops upon which they depredate. Of the one hundred selected 

 species, only about ten would come into the first class, about forty into 

 the second, and the remaining fifty into the third class. 



Of these one hundred species, twenty-seven are Coleoptera, or beetles, 

 and their larvce ; thirty-five are caterpillars, or larvae of the Lepidoptera ; 

 three belong to the Orthoptera, or grasshopper order; four to the Hem- 

 iptera, or bugs proper; twelve to the Homoptera, including the leaf- 

 hoppers, and the leaf and bark lice ; four to the Hymenoptera, or wasp 

 and bee order ; and fifteen to the Diptera, or two-winged flies. 



We moreover find that fifty-two, or a little more than half, are injuri- 

 ous to fruits or fruit trees ; twenty-six to vegetables ; fourteen to grain ; 

 five are general feeders ; and three are injurious to the domestic animals. 



Of the fifty-two species injurious to fruits, there are injurious to the 

 apple, sixteen ; to the pear, five; to the peach, two; to the plum, two; 

 to the quince, one ; to the grape, seventeen ; to the currant, four ; to the 

 blackberry, one ; to the raspberry, one ; and to the strawberry, three. 



Of the sixteen species injurious to the apple, four belong to the first 

 class, namely, the round-headed borer, the codling moth, the canker- 

 worm, and the oyster-shell bark-louse. Four belong to the second class — 

 the flat-headed borer, the apple curculio, the tent caterpillar, and the 

 ap])le root-louse. The other eight belong to the third class, besides 

 which there is a considerable number of minor noxious insects which 

 come into the fourth class. 



Of the five species more or less injurious to the i)ear, none are of the 

 first cla.ss, two are of the second classs — the pear flea-louse, i^Fsyl/a pyri^ 

 and the lined plant-bug, {Phytocoris lineolaris), and three of the third 

 class. 



Of the two species injurious to the peach, both are first class, the 

 plum and peach curculio, [Conotra-clulii 7iemtphar), and the peach-root 

 borer, (JEgeria exitiosa). 



