20 CORN AND GRASS. 



journals ; but I cannot myself see any cause for great anxiety on this 

 matter any more than with regard to others of our ordinary corn 

 insect pests. Last year being a hot season, especially favourable to its 

 prevalence, it was to be presumed it would be present ; but so far as I 

 am aware, this was not to anything like the extent to which it was 

 reported in the hot season of 1887. In that year, the second of its 

 recorded presence as a Wheat and Barley stem pest with us, it was 

 reported (with specimens accompanying, or by contributors well con- 

 versant with the attack) from more than seventy-two localities in 

 England, and about twenty in Scotland, these centres often repre- 

 senting districts, and sometimes many miles of area of attack ; as for 

 instance, in the north of Scotland, whence on the 29th of August, Mr. 

 John Milne, of Inverurie, Aberdeenshire, wrote me (with specimens 

 accompanying) that traces of the insect could be found in every field 

 along the coast from Aberdeen to Cromarty, and inland for twenty-five 

 to thirty miles. 



Yet, notwithstanding this widespread prevalence in 1887, in the 

 following year I only received about six reports of presence, and of 

 these only one mentioned the attack as being prevalent in that district; 

 and last year attack generally seemed hardly worth alluding to. 



The infestation may commonly be known by the attacked Barley 

 or "Wheat straw elbowing down (as figured at p. 19) just above one of 

 the lower knots in the stem, consequently on this part being weakened 

 by the continuous feeding of the little maggot of the brown gnat midge, 

 known as the Hessian Fly. Attack may be higher, or it may be lower, 

 even at ground-level. Where it is may be known on examination by 

 the presence of the little flat brown chrysalids known as flax-seeds, 

 figured p. 19 at "2." 



It is a most unlikely thing that this infestation will ever take hold 

 here with our insular and changeable climate, as it does in Continental 

 countries, where a recurrence of weather suitable to its propagation 

 may come more or less yearly as a matter of course ; and it is to be 

 regretted that from some cause or other a popular and exaggerated 

 interest has become attached to the very mention of " Hessian Fly " ! 

 I fully believe that, excepting Corn Sawfly, we have no corn attack 

 which it so fully lies in our power to check increase of ; or I should 

 better say, no corn attack which can be so demonstrably, and even 

 arithmetically, proved to lie so fully in our power to check much of the 

 increase of. 



On each farm where there has been Hessian Fly attack, we find at 

 thrashing time the chrysalids gathered up, without extra cost or trouble, 

 in the light screenings. If these are destroyed in any convenient way 

 there is an end of all increase from these. 



If, on the other hand, these flax-seeds are only flung aside from 



