726 
The recent appearance of the Hessian Fly. 
straw, — a good healthy plant will have power to grow past 
slight injury. 
Absence of wheat, barley, or rye, as a succeeding crop on 
land which has been infested, is a most important point. I am 
not aware that oats suffer under attack, but all crops other than 
cereals are safe. The kinds of corn which are firmest in the 
stem are considered least subject to attack, probably because 
the mouth parts of the maggot are so minute that it cannot 
effect serious injury where there is much silica in the straw. 
There is one point to be considered further which is of the 
very highest importance. 
Although the Cecidornyia destructor has been known as a corn 
pest of the most serious kind in various parts of North America 
for more than a hundred years, and has also been known for 
(say generally) half that time on the continent of Europe, and 
some of the Mediterranean islands, yet we do not know of it 
having occurred in Britain, — whence then has it come ? It is 
quite possible that the pupae may have been brought in infested 
straw and carried on to the ground in unrotted manure ; but my 
own fear is, as far as I can judge from information gained in 
the infested district of Hertfordshire up to the date of writing 
(Sept. 27) that it may be imported in screenings of wheat 
or barley from Russia, America, or other countries liable to 
Hessian fly attack. 
I am aware, besides, that the general coincidence of attack, 
and of the presence of foul corn in the infested district ; of 
its special occurrence at one farm where the the feed corn was 
used, and I am now endeavouring to procure details from com- 
petent reporters on this subject, both with regard to imported 
straw and likewise to the use possibly made of sweepings of 
damaged and infested wheat or barley from corn ships. The 
corn to be suspected is what is now being, or shortly, or during 
the winter will be, exported ; because the Hessian fly is recorded 
as hybernating in Russia in its pupal state, consequentl}' may 
easily be conveyed in the material wherein it lies. 
As the attack of Hessian fly has never before been recorded in 
England on any reliable authority, there is reason to hope that 
there are climatic reasons against its thriving in this country, 
and that by judicious enquiry leading to a knowledge of how 
it is now being brought in, we may at small expense rid 
ourselves of this addition to our agricultural burdens. But it 
should be borne in mind that as yet only a small proportion of 
those whose interests are at stake are well enough acquainted 
with the attack to discriminate between it and the other corn 
injuries, and it is of the highest importance that no reports 
