f 
128 Observations on the various Insects 
the flies hatcli and crawl out of the earth, with their little wings 
crumpled up, and climbing up the side of a clod or any perpen- 
dicular surface before they get dry, they expand and become the 
proper organs of flight. These, as well as the following species 
of flics, are comprehended in the Order Diptera, and form 
the Family MuscTD^ : the Genus comprising them is called 
Anthomyia by Meigen,* and the species, from its attacking the 
cabbages, is named by Bouche| — 
9. A. Brassicse, the Cabbage-fly. The sexes of this fly differ 
materially in aspect : the male is ashy grey, very bristly ; the 
large compound eyes nearly meet on the crown of the head, which 
is hemispherical : there are three minute eyes at the base of the 
crown ; the face is silvery-gray, almost white in some lights, with 
a long black streak on the forehead, pointed behind, below which 
are the black and triarticulate horns, the basal joint of which is 
small, the second large, the third the largest and oval, with a 
biarticulate pubescent bristle on the back, the basal joint being 
very minute : thorax oblong, the sides whitish, with three faint 
interrupted stripes down the back; body shining gray, rather 
small and elliptical, tapering to the apex, with a black stripe 
down the back ; the edges of the segments and the region of the 
scutel black also : two wings incumbent in repose, ample, trans- 
parent, iridescent, the longitudinal nervures reaching the pos- 
terior margin, with two transverse ones towards the disc ; balancers 
ochreous ; six legs black and spiny ; thighs and shanks simple ; 
feet five-jointed, terminated by two little claws, and two largish 
pale leathery lobes (fig. 32). The female is of an uniform ashy- 
grev, excepting the silvery-white face and pale sides of the 
thorax : the eyes are remote, with a broad black stripe between 
them, shading into chestnut-colour in front : the abdomen is 
stouter, and conical at the apex, and the wings have an ochreous 
tinge at the base (fig. 33) length, nearly \ of an inch ; expanse 
of wings, almost ^ an inch. 
These flies are on the wing the whole of summer, and there 
are consequently several generations of the maggots which are 
for many months eating passages in the stalks and roots of the 
cabbage and turnip tribes, thus causing them to become rotten 
as soon as they are subjected to wet and frost. Many of the flies 
no doubt live through the winter, secreted in holes and crevices, 
and some of the pupae do not hatch until the spring : in one in- 
stance the maggots and pupae were taken from the roots at the 
same time, the 19th of June, and the flies began to hatch on the 
* Curtis's Guide, Gen. 1287. 
t Natiirg. der Garten-Insccten, p. 131. 
% For the structure of the mouth, dissections, &c., consult Curtiss Brit. 
Eiit., pi. and ibl. 768, Hydrutaa, an allied genus. 
