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THE RUSSIAN PARASITE OF THE HeEsstIAN Fiy.—Miss Eleanor A. Ormerod, 
the eminent consulting entomologist of the Royal Agricultural Society of England, 
in a communication to the Mark Lane Hxpress, thus refers to the discovery of 
this parasite :— 
_ “Tt is announced in the United States that Professor C. V. Riley, the well- 
known entomologist to the United States Department of Agriculture, has intro- 
duced into that country living specimens of Semiotellus nigripes, a Russian 
parasite of the Hessian fly, in order to acclimatize it. By its aid he hopes to 
practically exterminate the pests in that country. Curiously enough he obtained 
this parasite from England, and it is said that quite a number have been reared 
for the purpose. If this is the case, there should be no difficulty in the way of 
adopting the same means of getting rid of the Hessian fly in this country, and 
it would be interesting to have Miss E. A. Ormerod’s opinion on the subject.” 
My opinion is that, quite certainly, it would be worse than useless (in this 
country) to make any such attempt. In the United States of America things 
are on a very different footing. There are differences in temperature, conditions 
of climate, and also of area of cropping, and other agricultural arrangements 
which must affect this question. Likewise there are special arrangements at the 
Government experimental stations for rearing insects, and skilled Government 
entomologists who can trustworthily examine the collections before they are 
turned loose on the conntry. 
The parasite fly (the Semzotellus nigripes) is only about onel line long, and 
without the help of a magnifying glass and some technical knowledge it would 
be impossible for any but skilled entomologists to be certain whether many pests 
were not included amongst the parasites which they set free. Also it is to be 
remembered for the most part insects pair, lay eggs, and die very shortly after 
they make their appearance from the chrysalids, but even supposing these 
minute creatures lived on awhile, where are they to be taken to ? 
We do not know what corn is infested until attack is thoroughly set up, for 
the most part till the mischief is so advanced that the time for action of the 
parasite is past; and at a vast expense the intended destroyers would in many 
cases be carried where there was nothing to destroy. 
This work of rearing could not be done on a broad scale—that is, by collec- 
tions from the threshing machine by farmers—and the payment to a staff of 
collectors. rearers, and distributors would involve enormous outlay. 
The present plan of destroying the Hessian fly chrysalids in the fine 
screenings is much the safest, and also has, for this country, the stated approval 
of Prof. Riley himself. It is easily done, costs scarcely anything, and causes no 
loss; and thus, though we destroy the parasites (of which there are several 
kinds), we also quite certainly destroy the pest. 
8 (EN.) 
