588 
DIPTEEA. 
letter by Mr. Christopher Gullet, written in 1771, and 
published in the “Philosophical Transactions” for 1772. 
“ What the farmers call the yellows in wheat, and which 
they consider as a kind of mildew, is, in fact, occasioned 
by a small yellow fly, with blue wings, about the size of 
a gnat. This blows in the ear of the corn, and produces 
a worm, almost invisible to the naked eye ; but, being seen 
through a pocket microscope, it appears a large yellow mag- 
got, of the color and gloss of amber, and is so prolific that 
I distinctly counted forty-one living yellow maggots in the 
husk of one single grain of wheat, a number sufficient to 
eat up and destroy the corn in a whole ear. One of those 
yellow flies laid at least eight or ten eggs, of an oblong 
shape, on my thumb, only while carrying by the wing 
across three or four ridges.” 
In 1795, the history of this insect was investigated by 
Mr. Marsham,* and since that time Mr. Kirby, f Mr. Gorrie, 
and Mr. Shirreff J have also turned their attention to it. 
The investigations of these gentlemen have become very 
interesting to us, on account of the recent appearance in 
our own country, and the extensive ravages, of an insect 
apparently identical with the European wheat-fly. The 
following account of the latter will serve to show how far 
the European and American wheat-flies agree in their essen- 
tial characters and in their habits. § 
The European wheat-fly somewhat resembles a mosquito 
in form, but is very small, being only about one tenth of an 
inch long. Its body is orange-colored. Its two wings are 
transparent, and changeable in color ; they are narrow at 
the base, rounded at the tip, and are fringed with little hairs 
on the edges. Its long antennae, or horns, consist, in the 
females, of twelve little bead-like joints, each encircled with 
* Transactions of the Linncean Society, Vol. III. p. 142, and Vol. IV. p. 224. 
t Ibid., Vol. IV. p. 230, and Vol. V. p. 96. 
$ Loudon’s Magazine of Natural History, Vol. II. pp. 323 and 448. 
§ See also my article on wheat insects in the New England Farmer, for March 
31, 1841, Vol. XIX. p. 306. 
