30 
THE WHEAT-STRAW WORM. 
(Isosoma tritici , Riley.) 
Order, Hymenoptera. Family, Chalcidid^:. 
[Plate II, Figs. 3 and 4.1 
This inject although first noticed less than four years ago, has 
now becXe a decidedly injurious enemy to wheat m Southern lUi- 
S’r£n y’^“t&ndtof dollars annually There is more- 
over no reason to infer that it has yet reached its limit, although 
it has already become, locally, at least as expensive a guest of the 
wheat farmer as the Hessian fly. 
On the other hand, these injuries and losses, serious as they are, 
mav certainly be almost perfectly controlled and prevented by sim- 
nle^ easy and inexpensive measures, which each may take mdividu 
nl!v without depending on his neighbors for cooperation, provided 
onlv that the characte? s and the life-history of these insects are 
understood This is, in fact, one oi those simple and satisfactory 
cases where a mere knowledge of the life history oi the injurious 
insect is sufficient to suggest effective measures tor i s destruction 
without awaiting the issue ot tedious and often difficult and expen 
sive experiment. . , 
These facts will certainly justify a full and careful discussion o 
the wheat-straw worm, and make it especially important that a 
thorough knowledge of it be widely disseminated among those m- 
terested in wheat culture m Southern Illinois It is tiue that tms 
species has already been treated at considerable length m the 
eleventh report of this office, m an article by Ripfi T * * ' 
but unfortunately at the time when this report was written, the 
wheat-straw worm had not yet been distinguished from a very differ- 
Int species which is probably one of its parasites; and, as a con¬ 
sequence of this confusion, several statements were made which 
involved not only technical, but practical errors. It is now apparent 
that this species was there given the wrong generic name, that the 
adult or imago described did not belong to the same species as t 
larva, that the life history of the two species was mingled, and that 
important but mistaken practical inferences were drawn from an 1 - 
correct supposition that most of the adults were winged. Ii seems 
indispensable, therefore, that the matter should be cleared up, and 
economic recommendations made, based on a complete acquai - 
ance with the habits and life history of the species; but it is pro 
per that, in presenting this account, I should disclaim all ciedit loi 
,v 
