1(50 



power to tear up the tissues of the plant, as is done bj" the Frit Fly and Wheat- 

 stem Magji^ot, because they have not the hooked jaws ; but they do effect a certain 

 amount of penetration, for they are frequently found partially embedded in hollows 

 in the stem of the plant they arc infesting. The Wheat-stem Maggot is hatched 

 from beautiful white grooved and elongated eggs, which are laid upon the uppei- 

 surface of the leaf, sometimes at a considerable distance from the axil. When the 

 young maggot hatches, it like the otheis referred to above, works its way down 

 into the t>hoot and destroys the central leaf. It tears the tissues apart and eats a 

 gallery up the centre of the shoot. In the summer brood the maggot occurs at the 

 base of the top, or ear-bearing joint, and by consuming the lower portion causes 

 the ear to die and turn conspicuously white (" Silver-top ") before the uninjured 

 plants have shown any sign of ripening. 



The perfect forms of these insects are extremely unlike. The Frit Fly is 

 shown at Fig. 1 very much enlarged. The colours are black and yellowish-white. 

 It is a ver}' small insect, large specimens being only about Jj of an inch in 

 length. They are extremely active and hard to observe. 



The fly of the Wheat-stem Maggot is a slender yellowish-green fly, \ of an inch 

 in length, with three dark lines extending down the back. Byes golden-green, when 

 the fly is alive. 



The Hessian Fly is adelicate dusky gnat, well shown in Miss Ormerod's excellent 

 figure (No. 3,) where it is represented magnified and enlarged. 



The somewhat remarkable popular name of the Frit Fly is explained by Miss 

 Ormerod and Prof. Garman as follows : — 



" Besides the attack to the young growing plant, great damage was recorded 

 formerly in Sweden from the second or summer brood, the maggots of which fed on 

 the soft grains in the ears of barley, and thereby caused the light worthless develop- 

 ment of the corn, known in Swedish as * frits.' whence the name of the fly. 

 (Ormerod, E. A. Manual, 1890, p. "74.) 



"The fly was long ago named Oscinisfrit by the illustrious Linnaeus, who also 

 made record of its injurious habit, stating that in 1750 the annual loss from its 

 depiedations in Sweden alone reached 100,000 gold ducats." " From the accounts 

 of the Frit Fly given b}'' Curtis and Miss Ormerod it is evident that the insect works 

 on grain much like a small fly which I find in the grub state infesting wheat in 

 Fayette County, Kentucky. In structure and habit, as far as I have observed the 

 latter, it proves so like the Eurepean species, that it might perhaps be appropriately 

 named the American Frit Fly." (Garman, H., Kentucky Ag. Ex. Station. Bui. 

 30 August, 1890.) 



Of all the insects attacking grain crops in the Ottawa district last summer, the 

 American Frit Fly was by fur the most destructive. In all cases observed the Hes- 

 sian Fl}^ and Wheat-stem Maggot were found associated with it. The injury to the 

 plants was almost exclusively in the stools or root-shoots, and the usual summer 

 attacks of the two last named insects on the stems of grain were conspicuously 

 absent. On the other hand, the attacks upon the stools by the summer brood, in the 

 same manner as fall wheat is attacked in the autumn, were this year for the first time 

 observed. 



That the American Frit Fly was abundant in the locality previous to this season 

 was sho^rn by its presence in injurious numbers upon the grass patches at the Experi- 

 mental Farm during the seasons of 1888 and 1889. Indeed, it was so abundant that 

 in these years, as well as during last season, the extermination of some species of 

 grasses was threatened. 



Theie were peculiarities about the attacks of all these insects during last 

 season which would indicate that they may have been influenced by some meteoro- 

 logical conditions, and it is possible that Ihc.-e may have affected the growth and 

 maturing of grasses and grain in the early spring. A remarkable fact was the 

 enormous abundance of the perfect insects of the Wheat-stem Maggot in the month 

 of May. This was so great as to have caused fear of a serious destruction of the 

 wheat and barley crops. As a matter of fact, however, there was less injury both to 



