32 
In a brief note in the same publication for January 28, 1882, 
Prof. French gave some reasons for believing that rotation of crops 
would prevent injury by this insect. In the same month he pub- 
lished under the name of Jsosoma allynii, in the ‘‘Canadian Ento- 
mologist,”’ a full description of the adult of the parasite, Eupelmus, 
still under the impression that it was the imago of his wheat-straw 
worm. With this misunderstanding in mind, it is evident from the 
following paragraph extracted from this article, that this winged 
parasite (Hupelmus) emerges from the straw in July and August, 
while the true straw worm passes the winter in the wheat stem in 
the pupa state. This misconception of the facts will be found to 
have important implications, when we consider remedial measures. 
“About four-fifths of the larve observed changed to pupe and 
produced the imago, or died, the past season from July 20, when 
the first imago was found, to August 20, or, perhaps better, under- 
went their changes between July 8 and August 20; but I think this 
the effect of the dry season. Those examined the last of November 
were in the pupa state in the interior of the stalks down close to 
or in the substance of the joint, both in the fields and in my breed- 
ing jars. ‘Those were in the larva state the last of August. It is 
probable they pass the winter in the pupa state under ordinary 
circumstances to produce the imagines in the spring, and that those 
hatching during July and August perish without ovinositing.” 
Following the above is a description of a species of Isosoma bred 
from grass (Isosoma elymi) which must be mentioned here because 
it was afterwards erroneously identified with the true wheat Isosoma. 
March 4, 1882, Prof. Riley again takes up the discussion to good 
purpose. Having bred the larva successfully, he found the true 
imago to be a new species of Isosoma which he discribes as Isosoma 
tritict. He also gives an account of its habits,‘and points out the 
characters distinguishing it from the joint-worm, Isosoma hordei. In 
this article Prof. Packard is quoted as authority for the common 
occurrence of this straw worm in Virginia and other southern sec- 
tions. ‘lhe supposition of Prof. French respecting the hibernation of 
this species is confirmed by Prof. Riley, who says that it winters as 
larva or pupa, and issues in March and April, although after a late 
and warm autumn individuals emerged in December and January. 
Prof. Riley also determined ‘‘Isosoma’”’ allynii to be a parasitic species 
of Kupelmus. 
Next, in the “Prairie Farmer” for March 11, and again for May 27, 
Prof. French mentions and confirms Prof. Riley’s determination of 
his adult specimens as a species of HKupelmus, but announces that 
he has successfully bred a genuine Isosoma from wheat straws con- 
taining the straw worm, and believes this to be the same as his 
Isosoma eiymi bred from stems of grass, and described in the “Cana- 
dian Entomologist” for January 8, as already mentioned above. 
Again, in the “Canadian Entomologist” for March, he reiterates 
this view, and mentions the common characters of the forms. 
It is important to note, however, that two of these are inaccurate, 
the head and prothorax of Isosoma tritici being smooth and shining 
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