FRIT FLY. 



7a 



present in Franco, Germany, and Sweden, where it attacks 

 both Oats and Barley. With us the attack has, as far as I 

 am aware, been ahnost entirely confined to Oats and is caused 

 by the maggot feeding in the heart of the young Corn-plant a 

 little above ground-level, and eating away the centre, so that 

 the shoot above the eaten part is destroyed, and the damage 

 that is going forward then becomes noticeable from the injured 

 shoots turning brown and withering, instead of continuing 

 their growth. 



Oscinis vastator : perfect fly, nat. size and magnified; and attacked plant, 

 with maggot inside. (The Oscinis vastator of Curtis bears such a strong resem- 

 blance to tlie Oscinis frit — even if it is not absolutely the same — that I have 

 used Curtis's figure to give the appearance of the insect and its method of 

 injury). 



The maggot is about the eighth of an inch long, whitish, 

 legless, cylindrical, bluntly pointed at the head-end, which is 

 furnished with a strong pair of curved mouth-hooks, and on 

 each side near the head it has a branched spiracle. At the 

 blunt hinder extremity it has two projecting wart-like spiracles. 



The chrysalis is rather smaller than the maggot, cylin- 

 drical, and rather more pointed at the front than at the 

 hinder extremity, which, from the strong projection of the 

 two wart-like processes, has the appearance of being cleft, or 

 almost bluntly forked, and for a time, after the maggot has 

 changed to the chrysalis state, the branched external spiracles 

 (or air-tubes) on each side of the head-extremity are very 

 plainly observable. 



In 1888, the only year in which we have record of this 

 attack being prevalent to an observably serious extent in this 

 country (when many enquiries and specimens were sent to 

 me), I found that about June 27th the maggots were turning to 

 chrysalids amongst the outer leafage of the destroyed shoots, 

 and towards July 9th, Frit Flies were appearing from the 



