554 
HYMENOPTERA. 
of the disease, would prove to be some species of Cecidomyia^ 
allied to, hut distinct from, the Hessian fly; and that they, 
Avhile in the larva or pupa state, had been preyed upon and 
destroyed by the Eiirytoma. The larva3 of the Hessian fly 
are often destroyed by a somewhat similar Chalcidian para¬ 
site, great numbers of Avhich have been observed, in their 
winged form, in wheat-fields, and have then been mistaken 
for Hessian flies. 
The body of the JEurytoma Hordei is jet-black, and slightly 
hairy. The head and thorax are opaque, and rough with 
dilated punctures. The hind body is smooth and polished. 
The thighs, shanks, and claw-joints are blackish; the knees, 
and the other joints of the feet, are pale honey-yellow. The 
females are twelve or thirteen hundredths of an inch lono;. 
The males are rather smaller, and are distinguished from the 
females by the following characters. They have no piercer. 
The joints of their antennae are longer, and are surrounded 
with whorls of little hairs. The hind body is shorter, less 
pointed behind, and is connected with the thorax by a longer 
stem or peduncle. These insects are very active, and move 
by little leaps ; but the hindmost thighs are not thickened. 
About eight years ago, some of these insects, that had come 
from a straw bed in Cambridge, were shown to me. They 
had proved very troublesome to children sleeping on the 
bed; their bites or stings being followed by considerable in¬ 
flammation and irritation, which lasted several days. So 
numerous were the insects, that it was found necessary to 
empty the bed-tick and burn the straw. Since that time, 
I have heard nothino; more either of the insects or of the 
disease of barley-straw in this part of the country. 
My attention was again called to the history of the barley- 
straw insect by an article on the joint-worm, published at 
Albany in “ The Cultivator,” for October, 1851. The ac¬ 
count given in this magazine, by Mr. Rives, of the ravages 
of the joint-worm in the wheat-fields of Virginia, and the 
remarks by Dr. Fitch on the peculiar affection of the wheat- 
