STATE AGRICULTURAL SOCIETY. 
843 
BLACK-LEGGED BARLEY-FLY. THE LARVA. 
viiii 138) that th e worms lying in the swollen part of the barley 
stalks, are about one-tenth of an inch in length, and of a yellow or 
straw color; and that, in the month of November, they appeared 
to have passed from the larva to the chrysalis state. They live 
through the winter unchanged in the straw, many of them in the 
stubble of the field, while others are carried away when the grain 
is harvested. When the barley is threshed, numerous small 
pieces of the diseased straw, too hard to be broken by the flail, 
will be found among the grain. Some of these may be separated 
by the winnowing machine, but many others are too large and 
heavy to be winnowed out, and remain with the grain, from which 
they can only be removed by the slow process of picking them 
out by hand. 
A few pieces of the diseased barley straw were furnished to 
Dr. Harris, who found in each of them several small whitish 
maggots, each of these being imbedded in the thickened and solid 
substance of the stem, in a little longitudinal hollow, of the shape 
of its own body, its presence being known by an oblong swelling 
upon the surface. In some pieces of straw the swellings were so 
numerous as greatly to disfigure the stem, the circulation in 
which must have been very much checked if not destroyed. Early 
in the following spring these maggots entered the pupa or chry¬ 
salis state, and on the fifteenth of June the perfected insects 
began to make their escape through minute perforations in the 
straw, which they gnawed for this purpose. The insects con¬ 
tinued to release themselves from their confiuement till the fifth 
of July, after which no more were seen. Instead of a midge or 
two-winged fly similar to the Hessian fly which he confidently 
looked for these maggots to produce, Dr. Harris says it was 
“ much to my surprise, they proved to be minute four-winged 
Ichneumon-flies, which are parasitical, preying in the larva state 
on the bodies of other insects.” These were described in the 
New England Farmer for July 23d, 1830 (vol. ix., p. 2) under the 
name of Eurytoma Hordei. At that time Dr. H. supposed the 
Semiotellus destructor, (of which we have spoken on a preceding 
page,) the parasite which destroys the larva of the Hessian fly, 
to be a species pertaining to this same genus Eurytoma. This 
error contributed still further to impress him with the view that 
this barley fly, like that, was a parasite which had destroyed a 
midge similar to tho Hessian fly, and had thus come out in its 
