INSECTS 

 INJURIOUS TO YEGETATIOJ^ 



CHAPTEE I. 



INTRODUCTION. 



Insects defined. — Bkain and Nerves. — Air-pipes and Bkeatiiixg-hoi.es. 

 — Heart and Blood. — Insects auk produced fuom Kggs — Metamor- 

 phoses, OK Transformations. — Examples of Complete Thansforma- 

 TiON. — Partial Transformation. — Larva, or Infant State. — Pupa, 

 OR Intermediate State. — Adult, or Winged State. — Head, Eyes, 

 Antenn.e, and Mouth. — Thorax or Chest, Wings, and Legs. — Abdo- 

 men OK Hind-body, Piercer, and Sting. — Number of Insects compared 

 with Plants. — Classification ; Orders ; Coleopteha ; Oethoptera ; 

 Hemipteka; Neuropiera; Lepidopteua; Hymenoptera; Diptera; Other 

 Orders and Groups. — Eemakks on Scientific Names. 



THE benefits which we derive from insects, though 

 neither few in number nor inconsiderable in amount, 

 are, if we except those of the silk-worm, the bee, and the 

 cochineal, not very obvious, and are almost entirely beyond 

 our influence. On the contrary, the injuries that we suffer 

 from them are becoming yearly more apparent, and are 

 more or less within our control. A famihar acquaint- 

 ance with our insect enemies and friends, in all their forms 

 and disguises, will afford us much help in the discovery 

 and proper application of the remedies for the depredations 

 of the former, and will tend to remove the repugnance 

 wherewith the latter are commonly regarded. 



Destructive insects have their appointed tasks, and are 

 limited in the performance of them ; they are exposed to 



