INDIRECT INJURIES CAUSED BY INSECTS. 183 



Here also may be included the larva of the lon^- 

 legged gnat, (Tipula oleracea, L.) known in many parts 

 by the name of the grub, which is sometimes very pre- 

 judicial to the grass in marshy lands, and at others not 

 less so to corn. Reaumur informs us, that in Poitou, 

 in certain years, the grass of whole districts has been so 

 destroyed by it, as not to produce the food necessary 

 for the sustenance of the cattle ''. In many parts of 

 England, in Holderness particularly, it cuts off a large 

 proportion of the wheat crops, especially if sown upon 

 clover-lays^. Reaumur concludes from the observa- 

 tions he made that it lives solely upon earth, and conse« 

 quently that the injury which it occasions, arises from 



divided and the apples sliced, he directed the pieces to be laid separate- 

 ly, dressing two stetches with them and omitting two alternately, till the 

 whole field of eight acres was gone over. On the following morning he 

 employed two women to examine and free from the slugs, which they did 

 into a measure, the tops and slices ; and when cleared they were laid 

 upon those stetches that had been omitted the day before. It was ob- 

 served invariably, that in the stetches dressed with the turnips no slugs 

 were to be found upon the wheat or crawling upon the land, though they 

 abounded upon the turnips; while on the undressed stetches they were 

 to be seen in great numbers both on the wheat and on the land. The 

 quantity of sings thus collected was near a bushel.— Mr. Rod well is per= 

 suaded that by this plan he saved his wheai from essential injury. 



* Reaum. v. 11. 



* Two species are confounded under the appellation of the grub, the 

 larvae namely of Tipula okracea and cvrnmna, which last is verj' inju- 

 rious, though not equally with the first. In the rich district of Sunk 

 Island in Holderness, in the spring of 1813, handreds of aores of pasture 

 have been entirely destroyed by tSiem, being rendered as completely 

 brown as if they had suffered a three months droaghf, and destitute of 

 all vegetation except that of a few thistles. A s([aare foot of the dead 

 turf being dag up, 210 grubs were cosated in it ! and what furnishes a 

 striking proof of the prolific powers of tht-c insects, last year it was dif»- 

 Scult to find a single one. 



