146 INDIRECT INJURIES CAUSED BY INSECTS. 



and the grass devoured to the root.^ In 1835 the larvae of 

 this moth so infested some districts in Bohemia that Prince 

 Clary, by employing two hundred men for four and a half days, 

 collected twenty-three bushels, computed to contain four and 

 a half millions of caterpillars.^ 



^ Grasses both natural and artificial are attacked by the 

 larvse of several species of beetles. Those of Coccinella im- 

 punctata (ivhich with C. Argus Scriba, and some other species, 

 live on vegetable food) destroy, in Crermany, sainfoin, clover, 

 and tares ; those of Colaspis harhara^ in Spain, whole fields of 

 lucerne {Medicago sativa ^) ; and those of Galleruca Tanaceti, 

 natural pasturage, having greatly injured that of Mount Jura 

 in Switzerland in 1833.'^ Even the seeds of grasses have 

 their insect enemies. Mr. H. Gibbs stated at the meeting of 

 the Royal Agricultural Society, May 5. 1841, that generally 

 not one in a dozen of the seeds of the Foxtail grasses (Alope- 

 curus) vegetate, owing to their vitality being destroyed by a 

 small orange-coloured grub {Cecidomyia ?).^ 



Most of the insects I have hitherto mentioned attack our 

 crops partially, confining themselves to one or two kinds only ; 

 but there are some species which extend their ravages indiffer- 

 ently to all. Of this description is the Pyralis (f^ frumentalis, 

 which moth, Pallas tells us, is an almost universal pest in the 

 government of Kasan in Russia, often eating the greater part 

 of the spring corn to the root.^ To this we are fortunately 

 strangers ; but another, well kno wn by the name of the wire- 

 worm, causes annually a large diminution of the produce of 

 our fields, destroying indiscriminately wheat, rye, oats, and 

 grass. This insect, which has its name apparently from its 

 slender form, and uncommon hardness and toughness, is the 

 grub of one of the elastic beetles termed by Linne Elater line- 

 atus, but by Bierkander, to whom we are indebted for its 

 history, Segetis'^ {Agriotes lineatus Eschscholtz). The late 



1 Farmer's Mag. iii. 487. 



2 KoUar on Ins. injurious to Gardeners, &c. 105. 126. 



3 Dufour, Ann. Sac. Ent. de France, v. 372. 



4 Ibid. iii. 19. 



5 Gardener's Chronicle, 1841. p. 311. 



6 Pallas's Travels in South Russia, i. 30. 



7 Marsham in Communications to the Board of Agriculture, iv. 412. Plate viii. 

 Jig. 4. and Linn. Trans, ix. 160. 



