546 
THE STUDY OF INSECTS. 
ruined at the outset. The appearance of these insects 
when in the ground, as seen through the glass side of one 
of our root- 
cages, is 
shown in 
Fig. 657. 
There 
is a vast 
number of species of click- 
beetles; more than five hun- 
Fig. 658.—Larva of Cryptohypnus abbrt . 
via/us : a , clypeus; b , mandible; c, 
maxilla; ef, gula; e, caudal segment. 
Fig. 659.—Larva of Drasterius elegant: 
F,c. 657.—A corn-plant growing in a root- '* maX “' a * 
cage infested by wire-worms and click- 
beetles (from a specimen in the Cornell 
Insectary). The spotted beetle represented dred haVC been described 
near the base of the plant is Drasterius 
elegans: that near the top of the plant is from North America alone. 
Agriotes mancus. 
It is quite difficult to sep¬ 
arate the closely-allied species, as there is but little variation 
in shape and color. The larvae also show comparatively 
