56 MECHANICAL FUNCTIONS. 



variety of this tribe are known under the common ap- 

 pellation of bugs. Most of them fly only in the night, 

 and some of the larger, make a deep toned sound with 

 their wings, so loud as to be heard many rods distant. 



The larvae of some of this tribe, in consequence of 

 their living under the ground and destroying the roots of 

 plants, which serve them for food, are exceedingly de- 

 structive to the farmer. The perfect insects also some- 

 times make terrible desolation among the forest, and 

 other trees. 



The Blind Beetle. The Melolontha vulgaris, called 

 also Chafer, Blind Beetle, or more commonly Cock- 

 chafer, is one of these insects. 



Fig. 38. The larva of this beetle is 



known to farmers under the 

 name of the White worm, and 

 is represented by Fig. 38. The 

 eggs of these worms are deposi- 

 ted in the ground by the parent 

 insect, and when first hatched 

 are of very small size. As they 

 grow, they change their skins 

 several times, and at the end of four years during 

 which time they remain in the earth, they acquire the 

 size represented, having six legs, armed with strong 

 claws, and a reddish head. During its subterranean 

 residence, it lives on the roots of grass, sometimes com- 

 mitting the most deplorable ravages. When their num- 

 bers are great they cut off all the roots of the grass in 

 the richest meadows, leaving the turf entirely detached 

 and dead, so that it may be rolled up by the hands like 

 a carpet without the aid of a turfing knife. Under- 

 neath, the soil appears pulverized, and turned into a 

 soft mould like the prepared bed of a garden. In this, 

 the worms are seen coiled up and lying on their backs, 

 generally almost motionless. 



Some years since a poor farmer in Norwich, England, 

 suffered so much from these worms as to destroy all 

 his hopes, and the authority of that city out of compas- 

 sion, voted him 25 pounds to assist him under such a 

 calamity. This man and his servant testified, that they 



