STATE AGRICULTURAL SOCIETY. 
827 
HESSIAN FLY. PARASITES. 
The Hessian fly is everywhere followed up and destroyed by 
parasitic insects. The most common and important one of these 
was described by Mr. Say in connection with the Hessian fly, 
(Journal Academy of Natural Sciences, vol. i, p. 47,) under the 
name Ceraphron destructor. We present a carefully drawn figure 
of this insect, Plate 3, fig. 1. Entomologists have been much 
perplexed to determine the true generic place of this species, it 
being evidently not a member of the genus to which Mr. Say 
assigned it, or even of the family to which that genus pertains. 
It clearly belongs to the family Chalcididce. Mr. Westwood, 
from the imperfect figures accompanying Mr. Say’s description, 
at first supposed it was a member of the group Eulophides (In- 
tro'dnetion, vol. ii, p. 160) but the number of joints both to its 
feet and antennae exclude it from that group, and he subse¬ 
quently, as we are told by Mr. Curtis, (Jour. Royal Agricultural 
Society, vol. vi, p. 130) thinks it is perhaps a Pteromalus. Dr. 
Harris at first regarded it as an Eurytoma, but becoming aware 
this location was erroneous he finally concluded the genus Rhaph- 
itelus to be its true place. But independent of other discord¬ 
ances, its antennas indicate it to be a member of the group 
Pteromalides rather than that of Ormocerides where Dr. Harris’s 
conclusion would place it. The number of joints to its antennae 
exclude it from the extensive genus Pteromnlus, and of the seve¬ 
ral kindred genera in which these organs are twelve-jointed, that 
of Semiotus, Walker (which name being pre-occupied, Mr. West- 
wood proposes to modify to Semiotel/us ) seems to be the only 
one from which it is not decidedly excluded by some one or more 
characters. With this genus it appears to fully coincide, having 
the antennae in the male thread-like, in the female perceptibly 
though but slightly thicker towards their tips, the apical joints 
being compacted into a linear mass in the one sex, an oval one 
in the other, the thorax punctured, and other characters which 
will appear from the full description presented herewith. So 
far, therefore, as I am able to judge from the characters assigned 
to this genus without any of the foreign species in my hands for 
a comparison, I am induced to regard this as its true location. 
And I may further observe, that a parasitic destroyer of the 
Apple-tree caterpillar which 1 described in my second Report 
under the name Cleonymus Clisiocampee, I now see is co-generic 
with this destroyer of the Hessian fly. I stated its antenme to 
