INSECTS 
INJURIOUS TO VEGETATION. 
CHAPTER I. 
INTRODUCTION. 
Insects defined. — Brain and Nerves. — Air-pipes and Breathing-holes. 
— Heart and Blood. — Insects are produced from Eggs. — Metamor- 
phoses, or Transformations. — Examples of Complete Transforma- 
tion. — Partial Transformation. — Larva, or Infant State Pupa 
or Intermediate State. — Adult, or Winged State. — Head, Eves 
Antennas, and Mouth. — Thorax or Chest, Wings, and Legs. — Abdo- 
men or Hind-body, Piercer, and Sting. — Number of Insects compared 
with Plants. — Classification ; Orders ; Coleoptera j Orthoptera • 
Hemiptera; Neuiioptera; Lepidoptera; Hymenoptera; Dipteha; Other 
Orders and Groups. — Remarks on Scientific Names. 
T HE 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 
moie or less within our control. A. familiar 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 for mer, 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 
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