332 Annual Eeport fof 1888 of the CunsuUi.wj J^ntomologist. 
Insect Attacls upon Corn. 
Dui'ing the fiivib half of tlie hist season injurious insect 
attack of various kinds of maggots destructive to young corn was 
also unusually prevalent, and in some cases unusually serious. 
During the early part of the summer much injury was 
reported as being caused to young wheat and oat plants by fly 
maggots feeding within the central shoot. No difference was 
observable in the method of injury to the two kinds of crop, 
but on microscopic examination of the small white maggots 
that caused it, those infesting the oat plants and those in the 
Avheat plants proved to be clearly distinguishable from each 
other. These I traced respectively through their changes of 
condition up to the perfect flies, which proved in the case of the 
wheat to be Itijlcmia coardata of Fallen, or " wheat bulb fly," 
and in the case of the oats to be the Oscinis frit of Linnteus, 
commonly known as the " frit fly."' 
The ''Frit Fli/."— This frit fly is a small, very brightly 
glistening, black two-winged fly, rather under the eighth of an 
inch in length, the legs black, with some amount of yellow 
or brown-yellow in the feet, the wings transparent, somewhat 
brown at the fore-edge. The fly, though very small, is notice- 
able from its peculiar habit of dancing and skipping about. 
The method of attack is for the female to lay her eggs on the 
under side of a leaf, the maggots from these gnaw their way 
into the heart of the young_ plant, and there eat away the centre 
until the shoot above the eaten part is consequently destroyed. 
The damage that is going forward then becomes noticeable 
(as it did last summer in the infested districts mainly during 
June) from the appearance of the withered shoots. The maggot 
is whitish, or yellowish, cylindrical, legless ; when full grown 
about the eighth of an inch long ; somewhat pointed at the head, 
which is furnished with a pair of strong curved mouth hooks, 
and on each side near the head is an external branched spiracle. 
At the blunt hinder extremity the maggot has two projecting 
wart-like spiracles. 
When full fed it leaves the inside of the plant and turns in 
the remains of the withei'ed leaves outside to a chestnut-brown 
chrysalis, rather more pointed at the fi-ont than at the hinder 
extremity, which from the projection of the two wart-like pro- 
cesses has the appearance of being deeply cleft. The flies from 
the chrysalids sent me began to appear about July 9. 
Up to the present year I am not aware of the attack of the 
Ocinis frit having been seriously injurious in Britain, although 
the fly has been known to be present, and some amount of 
