INJURIOUS INSECTS. 237 



our agricultural papers it is still spoken of as solely the Tipula 

 tritici of Mr. Kirby. 



In this article, and another presented about a year afterwards 

 ( Trans. Lin. Soc. vol. v. p. 96), Mr. Kirby gives a large number 

 of most interesting and valuable observations upon this insect, the 

 correctness of wliich, generally, more recent investigations have 

 fully attested. With regard to its abundance at that time, he says 

 he could scarcely pass through a wiieatfield, in which some florets 

 of every car were not inhabited by the larvae ; and in a field of fifteen 

 acres, which he carefully examined, he calculated that the havoc 

 done by them would amount to five combs (twenty bushels). 



From this time, we have met with no notices of the wheat-fly, 

 except occasional references to the articles above mentioned, until 

 the year 1823, when, and for a few of the following years, it again 

 appeared in such numbers and with such havoc in several of the 

 counties of England and Scotland, as to elicit communications in 

 the magazines from seve.-al writers. In some districts of Scotland, 

 its devastations would seem to have approached in severity what has 

 been experienced upon this side of the Atlantic ; for " Mr. Gorrie 

 estimates the loss sustained by the farming interest in the Carse of 

 Gowrie (the rich alluvial district along the Isla and its tributaries in 

 Perth and Forfarshire) by the wheat-fly alone, at 20,000Z. in 1827, 

 at 30,000Z. in 1828, and at 36,000/. in 1829" {Encyc. of Agric. 3d 

 Lond. ed. p. 820. ^ 5066). And Mr. Bell, writing from Perthshire, 

 June 24, 1830, says, "We are anxious to have the present cold 

 weather continue for another ten days, to prevent the eggs from 

 latching, until the wheat be sufficiently hardened and beyond the 

 state which aff'ords nourishment to the maggot. Another year or two 

 af the wheat-fly will make two thirds of the farmers here bankrupts" 

 Gardener's Magazine, vol. vi. p. 495). Mr. Gorrie, in a letter 

 lated at Aunat Gardens, Errol, Perthshire, Sept. 1828 {Loudon^s 

 Mag. of Nat. Hist. vol. ii. p. 292), solicits information "on the 

 mture and mode of propagation of a fly which has this year de- 

 stroyed about one third of the late sown wheat all over this country." 

 He describes a small yellow caterpillar, one eighth of an inch long, 

 IS numerous in the young ears of wheat, completely devouring the 

 young milky grain, becoming torpid in about twelve days, and in 

 :ix days more changing to a small black fly. In a subsequent com- 

 iiunication, Aug. 1829 (p. 323), he corrects the latter part of the 



