HESSIAN FLY. 
51 
Prof. F. M. Webster, of Lafayette, Indiana, U.S.A., who lias 
especially studied the subject of winter presence of the larva for the 
last three years, considers that it may be detected by peculiarities of 
the growth and colour of the infested plant. Whilst these pages were 
passing through the press, I was favoured by him with notes on 
the subject, of which I give below some parts (together with the 
accompanying figure), as follows :— 
Plant of young Wheat, showing position of Hessian Fly maggot at “a.” 
(After Prof. Webster.) 
“ The above figure represents a Wheat-plant affected by Hessian 
Fly, the flax-seed or pupa being shown at a , where the insect is now to 
be found, just under the sheath of the plant. If the insect has not 
advanced to this stage of development, they will be of the same form, 
but of a whitish colour.” 
“ The plant itself has not tillered, the leaves are of a darker colour 
than those of a healthy plant, and proportionally broader. The central 
spindle-shaped leaf is missing, and the whole plant is only a bunch of 
rank-growing leaves. In any case the darker colour of the leaf, and 
the absence of the central leaf, together with the bunchy appearance 
of the part affected, will readily distinguish a fly-infested plant from 
one not injured. The yellow colour of some leaves is seldom observed, 
at this season of the year, on fly-infested plants.” — From circular by 
Prof. Webster on Hessian Fly maggot-attack to young Wheat. 
