CHAPTER II. 



INSECTS. 



INSECTS are easily distinguished from the other jointed animals by many salient characters. 

 They have one pair of antennae, two large compound eyes, composed of a great number 

 of facets, and sometimes one, two, or three simple eyes placed on the crown or front of 

 the head. In its adult condition an insect is composed of three different parts, which can 

 be most readily noticed in a wasp. There is the head, with the antennae and mouth-parts; 

 the thorax, to which one or two pairs of wings are attached above, and three pairs of legs 

 below ; and the abdomen. Insects breathe through openings, called " stigmata," in the sides of 

 the thorax and abdomen. They never possess more than six legs in the perfect state, the 

 abdominal legs present in caterpillars, etc., disappearing in the adult condition. They generally 

 pass through what is called a " metamorphosis," four different stages of life, called respectively 

 egg ; larva or caterpillar ; pupa, nymph, or chrysalis ; and imago, or perfect insect. 



Insects are divided into several large sections, of which the following seven are the most 

 important, and many entomologists prefer to include all insects under them : 



Sheath-winged Insects, or Beetles; Straight-winged Insects, or Earwigs, Cockroaches, 

 Soothsayers, Stick-insects, Crickets, Grasshoppers, and Locusts ; Nerve-winged or Lace-winged 

 Insects, or Dragon-flies and their relatives ; Stinging Four-winged Insects, or Ants, Bees and 

 Wasps, and their allies ; Scale-winged Insects, or Butterflies and Moths ; Half-winged Insects, 

 or Bugs and Frog-hoppers ; Two- winged Insects, or Flies. 



We proceed to notice these orders separately. 



SHEATH-WINGED INSECTS, OR BEETLES. 



BY THE REV. THEODORE WOOD, F.E.S. 



BEETLES are distinguished from most other insects by the fact that the front wings are 

 not employed in flight, but are modified into horny sheaths, which cover and protect the 

 lower pair while not in use. This arrangement, however, is also found in the Earwigs as well 

 as in the so-called " Black-beetle " and its allies, and it is to be noted that the wing-cases of 

 beetles lie evenly side by side together when the wings are folded, while the folding of the wings 



themselves is transverse as well as 

 is very great, upwards of 100,000 

 which about 3,400 have been taken 



The order is again divided into 

 which stand the predaceous beetles 

 English TIGER-BEETLE is a familiar 

 peaty heaths, and may be known 

 cases, marked with white spots, and 

 The legs are coppery. It flies with great 

 to wing as readily as a blue-bottle fly, 



Another representative of the 

 with coppery reflections. It is only 

 but abounds in France and Germany, 

 of the famous Processionary Moth, 

 checking their ravages in the great 



Familiar to almost all is the 

 in gardens, and easily recognisable 



Photo by W. P. Dando, 

 F.Z.S., Regent's Park. 



TIGER-BEETLE. 



The colouring of this 

 insect is bright green with 

 white markings and coppery 

 legs. 



681 



longitudinal. The number of species 

 having already been described, of 

 in the British Islands, 

 several smaller groups, first among 

 of the land. Of these the common 

 example. It is found on sandy and 

 at once by its bright green wing- 

 the metallic blue of the abdomen, 

 swiftness in the hot sunshine, taking 

 and feeds entirely upon other insects, 

 group is rich golden green in colour, 

 an occasional visitor to Britain, 

 where it feeds upon the caterpillars 

 and is largely instrumental in 

 oak forests. 



PURPLE GROUND-BEETLE, so plentiful 

 by the violet margin to the black 



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