356 



wanted, notch the ends, and tie a string around, as in making a kitej 

 or better use stiff Avire or a full hoop. Take inanila or even newspa- 

 per, cover all of one side with paste, and cover one section (one-fourth 

 of the "dome") with it, turning all tlie suri)lus paper inside. The other 

 three sections are covered with paper in the same way, turning the 

 surplus pai)er either inside or outside, as it would naturally go. A 

 bundle of rngs or cotton can be tied inside where tlie hoops cross to 

 receive the charge of bisulphide. Any of the chemical left after treat- 

 ing one hill can be carried with little loss to the next. This will make 

 a more substantial cover than one would at first think, even when made 

 of newspapers, as when dry the paste will make them very stiff, espe 

 (tially when there are several thicknesses of paper. The covers will also 

 be very resistant to the vapors of the bisulphide of carbon. 



THE IMPOKTEl) PARASITE OF THE HESSIAN FEY. 



Entomologists will have noticed in the last few reports of Professor 

 Kdey, as chief of this division, accounts of attempts which he has 



Fig. 36.—Entedo7i epigonns Walk.— enlarged (original.) 



made to introduce into this country one of the common European par- 

 asites of the Hessian fly, known as Semiotellus nigripes = Entedoti 

 epigonus Walker. With the assistance of Mr. Fred Enock, of London, 

 Professor Eiley several times distributed parasitised flax-seeds of the 

 Hessian fly to observers who were favorably located in this conutry. 

 The attempt which gave the best promise of success occurred in 1891, 

 when Professor Forbes, of Illinois, received a large number of parasitised 

 puparia and distributed them in a field, and later fonnd living speci- 

 mens of the parasite. Specimens have been cared for by Professor Cook 

 in the vicinity of Agricultural rollege, Mich. ; by Mr. James Fletcher in 

 the vicinity of Ottawa, Canada, and by Professor Forbes in Illinois. 



