INDIRECT INJURIES CAUSED BY INSECTS. 145 



cockchafer {Melolontlia vulgaris). This insect, which is found 

 to remain in the larva state four years, sometimes destroys 

 whole acres of grass, as I can aver from my own observation. 

 It undermines the richest meadows, and so loosens the turf 

 that it will roll up as if cut with a turfing-spade. These 

 grubs did so much injury about seventy years ago to a poor 

 farmer near Norwich, that the court of that city, out of com- 

 passion, alloAvedhim 25/., and the man and his servant declared 

 that he had gathered eighty bushels of the beetle.^ In the 

 year 1785 many provinces of France were so ravaged by 

 them, that a premium was offered by the government for the 

 best mode of destroying them. They do not confine them- 

 selves to grass, but eat also the roots of corn ; and it is to 

 feast upon this grub more particularly that the rooks follow 

 the plough.^ 



The larva also of another species of a cognate genus (Hoplia 

 'pulverulenta) is extremely destructive in moist meadows, 

 rooting under the herbage, so that, the soil becoming loose, 

 the grass soon withers and dies. Swine are very fond of 

 these grubs, and will devour vast numbers of them, and the 

 rooks lend their assistance. 



Amongst the Lepidoptera, the greatest enemy of our pas- 

 tures is the Charceas Graminis, which, however, is said not to 

 touch the foxtail grass. In the years 1740, 1741, 1742, 1748, 

 1749, they multiplied so prodigiously and committed such 

 ravages in many provinces of Sweden, that the meadows 

 became quite white and dry as if a fire had passed over them.'*^ 

 This destructive insect, though found in this country, is luckily 

 scarce amongst us ; but our northern neighbours appear occa- 

 sionally to have suffered greatly from it. In 1759, and again 

 in 1802, the high sheep farms in Tweedale were dreadfully 

 infested by a caterpillar, which was probably the larva of this 

 moth ; spots of a mile square were totally covered by them, 



1 Philos. Trans. 1741. 581. 



2 There would seem to be a prospect of cockchafers being made in some degree 

 to repay the previous injury they cause, if the statement in the newspapers 

 (June, 1841,) be correct, that M. Breard, mayor of Honfleur in France, and pro- 

 prietor of an oil mill, having offered one franc per bushel for cockchafers, pro- 

 cured seventeen bushels, from which he obtained twenty-eight quarts of good 

 lamp oil. A kind of grease has also lately been made from them in Hungary. 



3 De Geer, ii. 341. Amcen. Acad. iii. 355. 



VOL. I. 



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