HESSIAN FLY. 21 



neglect, or saved for any reason whatsoever, it is a certain thing that, 

 weather and circumstances permitting, the Hessian Flies from them 

 will attack next year's crop ; if destroyed there will be no further 

 trouble from them. 



Where circumstances do not allow the winter crop (as after infested 

 Barley) to be ploughed in, or otherwise treated, so as to destroy the 

 flax-seeds fallen from the stem, we have no apparent remedy, and we 

 must in this case hope that the "parasites," which are so frequently 

 brought under our notice, and which really do good in destroying the 

 pest when we are not able to do it (as above mentioned) much more 

 surely ourselves, will play their part rightly. 



Where flax-seeds have fallen, as many must, amongst the stubble 

 of the reaped cornfields where the plough is to be put in, the matter, 

 if requiring attention at all, can be met to some extent by treatment. 

 Deep ploughing, or ploughing with skim- coulter, so as to turn the 

 flax-seeds thoroughly down where the}' will not be brought up 

 again by subsequent agricultural arrangements, will quite certainly be 

 useful. 



Also burning the stubble is a well proved remedy, and would get 

 rid of many kinds of insect pests besides the one under consideration. 

 In most seasons this operation is neither very easily practicable nor 

 much needed, but last season (1893), when the exceptional heat and 

 drought would have allowed the firing, it would have cleared out the 

 ground remains of attack excellently. The right method of operation 

 is first to burn a narrow baud of stubble all round the field, this 

 effectually keeps the fire in the circumscribed area, and ensures safety 

 to hedges. In the opportunity of observation given by railway journey, 

 I have noticed fields and strips of fields safely fired, and the benefit in 

 clearing pests that we can get at no other way is great. 



But in our island we have great security from prevalence of serious 

 widespread attack, in our climate, and so far as Wheat is concerned 

 in our customary date of sowing, bringing up the autumn Wheat after 

 the time of the autumn brood of Hessian Flies having died ofi' ; and if 

 in the coming season we have ordinary climatal conditions, it may 

 reasonably be hoped that widespread mischief will be as little present 

 with us from this pest as in the years after the hot season of 1887 to 

 the hot season of 1893, when though bad in some localities, it could 

 not be described as a general trouble. 



Whilst the above note on Hessian Fly was passing through the press, 

 I was favoured by Mr. W. M. Schoyen, Conservator and Government 

 Entomologist at the Zoological Museum, University > Christiania, Avith 

 the following observation of the first recorded appearance of this pest, the 

 Cecidomyia destructor, in Norway. With the notes of locality, &c., given 

 below, Mr. Schoyen also placed in my hands a few specimens of Barley 



