INSECTS OF THE FIELD. 



79 



BEETLES are so common that nearly every person is familiar 

 with their appearance. Some are very small; those found in this 

 country are usually not larger than the 

 figure shown here. In some foreign 

 countries, however, they are found four 

 to six inches long. Observe the three 

 sections of the beetle. There are two pairs 

 of wings, the upper pair quite hard or 

 horny, covering the pair of fihny wings 

 beneath. These sheath-wings are pecul- 

 iar to the beetles. How many legs 

 have they ? Where are they attached to 

 the insect ? Find the eyes and observe 

 the shape of the mouth and feelers or 

 horns. The beetles go through much the same changes observed 

 in moths. In the case of the beetles, however, the larval 

 form is known as a grub. The white grubs found in the soil 

 are the larvae of large brown beetles. 



Fig. 31. A ground beetle, 

 one of the "sheath 

 winged " insects, very 

 destructive to cutworms. 



Fig. 32. Lady-bird beetles, or "lady-bugs." The straight lines represent the average 

 natural length. These beetles are very destructive to plant lice. 



Among the beetles we have a large number of very des- 

 tructive insects. There is, for instance, the potato beetle 

 which does so much damage to the potato plant by eating 

 the leaves. See fig. 33. The hard-shelled beetle lays her 

 orange-colored eggs on the under side of a leaf. These 

 eggs hatch into the soft-skinned larvre which eat the 

 leaves. The larvae change to pupae and these to the full- 

 grown winged insects. Since the larvae feed on the leaves a 

 simple remedy is to sprinkle some poison (Paris green) on 

 the leaves just before they begin to feed, or to destroy the 



