No. 105.] 
281 
DESCRIPTION OF THE CLEAR-WINGED WHEAT-FLY. 
Cecidomyia Tritici.— Kirby . 
The importance of full and accurate descriptions of every one of 
the several parts of a natural object, in order that it may be identified 
with certainty, is strikingly illustrated in the present species. For 
some years it has been supposed to be identical with the English 
wheat-fly; but those who are aware of the large number of both plants 
and animals in Europe, that have analogous representatives in this 
country so closely resembling them as to have been in many instan¬ 
ces for a long time considered identical even by accurate and experi¬ 
enced observers, could not but entertain doubts upon this point; and 
with the fifteen or twenty characters of this insect which could be 
gathered from different sources, I could still only say that our wheat- 
fly was probably the Tritici of Mr. Kirby, some of its prominent pecu¬ 
liarities seeming even to conflict with the descriptions given of that 
species. For instance, all that we could gather respecting the form 
of the joints of the antennae, was, that they were “ moniliform ;” 
and Messrs. Kirby and Spence, in their “Introduction to Entomology,” 
define this term to mean “ oval or globular joints, like a necklace of 
beads.” Now the joints of the antennae in our insect are oblong, 
and each has a marked contraction in its middle, thus approaching to 
an hourglass shape, a form the very reverse of “ oval” or 11 globular.” 
It was not until I saw the excellent figures and descriptions of Mr. 
Curtis, that I became well assured that our species was identical with 
the European. 
The common reader will get the most clear and definite idea of the 
appearance of the wheat-fly, by being told that it looks almost exactly 
like the wheat-worm with wings and legs added to it. These mem¬ 
bers, however, are so very small as to be scarcely recognized by the 
naked eyes, except when they are fixed intently upon the object. 
The head of the female Cecidomyia Tritici (Plate, fig. 1) is of an 
orbiculate or fiattened-globular form, with the eyes forming its peri¬ 
phery. These are large, occupying full two-thirds of the entire head. 
They are of a deep black color, and are separated from each other on 
the top of the head only by a slight and almost imperceptible cleft, 
so that when viewed in front they appear like a continuous broad 
