HESSIAN FLY 



35 



specimens herewith, from which you will see the flax-seeds are for the 

 most part to be found at ground level. There are also some stems 

 (apparently slender or delicate ones) entirely shrivelled up ; inside one 

 of these I found a brown pupa bearing a close resemblance to those of 

 the Hessian Fly, except that it seemed longer and not so flat. The 

 next found I put into a quill and send for your inspection herewith, 

 without removing from its abode." — (D. D. G.) 



The specimens sent I carefully examined, and could not find any 

 reason for considering them other than " flax-seeds," that is, Hessian 

 Fly puparia ; and the shrivelling of the stem seemed to me quite 

 attributable to the attack acting on an already weak growth. 



Mr. Gibb further noted that, — " This crop of Wheat was sown late 

 in November, and was kept in check by rabbits during the winter and 

 spring that few blades were to be found three inches in length until 

 well on in April, when, after harrowing and rolling (but no dressing 

 of manure), it grew very rapidly, and now looks like yielding 5 qrs. 

 per acre." 



On the 26th of July Mr. Gibb wrote that he had little to add 

 further regarding the Hessian Fly infestation, of which he had, as 

 above mentioned, sent specimens, but that "the presence of the pest 

 can be traced in most local crops of Wheat and Barley, but the 

 damage cannot be termed serious. The season having been so favour- 

 able for plants tillering or shooting afresh where injured by this or 

 stem maggot pests, crops of cereals are very much over the average." 

 In another part of the same letter, Mr. Gibb (referring to attack of 

 Diamond-back Moth) mentioned, regarding influence of weather on 

 growth of crops: — "The constant showers which have been very 

 trying to those engaged in haymaking operations, have caused a very 

 rapid growth of Swedes and other root crops." And two days later, 

 he noted that "yesterday and to-day we have had a change for the 

 better in the weather," thus showing the unfavourable weather had 

 lasted up to date. 



In the following letter, accompanying specimens of Hessian Fly 

 flax-seeds which I had asked for if still observable, it will be seen that 

 Mr. Gibb notices the large amount of presence of the pest, but that 

 this was less noticeable than it would otherwise have been on account 

 of the moist season having kept up the vigour of the plant. This was 

 written on the 25th of August, and, like the preceding observations, 

 from Ossemsley Manor Farm, Lymington, Hants : — " I have much 

 pleasure in being able to supply you with a few stems of Wheat and 

 Barley containing some specimens of Hessian Fly puparia in situ. In 

 some of these I believe you will find several ' flax-seeds ' clustering 

 around one stem. Unfortunately there is very little difficulty in 

 finding specimens, the pest having been severe, although the moist 



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