A AUI M p i AY AM C asd ki 
Hiftory of Tipula Tritici. FI 105 
Several fpecies of the genus Empis alfo ren dente the wheat fields, 
. often carrying off our Tipula i in their diminutive beaks. ` 
aug have now given you as complete an account of thefe infeéts as 
the obfervations of the prefent year enable me. Something {till re- 
mains to be done; for inftance, to afcertain the male, the hyberna- 
cula of the pupa, to collect further fa&s relative to the two new. 
Ichneumons, and, from obfervations taken in  fücceffive years, to deter- 
mine how far our crops of this grain depend upon the increafe or 
decreafe of the Zipula and its Jcbneumons. 3 
Cui bono? is a query often put to naturalifts; and the agricultu- 
rift perhaps will afk upon the prefent occafion, Can you inform us ` 
how we may prevent or diminith the ravages of thefe infe&ts? In 
reply to this, I would obferve, that the firft ftep. towards curing a 
diforder, is to find out its Gale In the prefent | inftance this is the 
. bufinefs of the naturalift, and this ;/ done. The intelligent farmet 
has no longer to afk what occafions the:mifchief ; all he has now to. 
do, is to aim at difcovering a remedy. | By: a fet of experiments firft 
made | upon ai {mal cele he may poffibly find out fome method that - 
will prevent this infect from laying its eggs in his wheat: thefe 
fhould commence as foon as the ear begins to quit the folium vagi- 
nans:or hofe ; ; and they ought to be continued till the germen is im- 
pregnated, or, to ufe the rural phrafe, the wheat is off the bloffom. 
Perhaps fümipations of tobacco ór fulphur, if made when the wind 
was favourable, might render the ear difagreeable | to this infect. 
Much of the i injury ' "Which this fly does, in. years peculiarly favour=. 
able to: its-increale, it i ds -pofüble, by fome:fuch means might be pre- 
vented ; :yet it is not certain that the total annihilation of it would 
ba ultimately beneficial [on But be it granted that our labours lead 
es > ad the 
(b) We are very apt to think, ‘that if certain noxious fpecies of animals AA "he anni 
hilated, it would be-a great benefit to the human race; an idea that drifes only from our 
“Wor V. E : a fhort- 
