xt] Flies 147 
hence their name Leather Jackets. The pupa is about 
the same size as the grub from which it is formed. 
Its abdomen is covered with a number of spines. Its 
head bears two horn-like projections (see Fig. 45 B). 
When the adult fly is about to come out the pupa 
moves to the surface so that its upper half is exposed. 
The empty cases are often a nuisance on putting 
greens. 
The flies themselves are too well known to need 
description. According to Curtis the eggs are laid 
as the insects fly or when they are at rest amongst 
the herbage and are propelled as from a pop-gun. 
This takes place in damp or shady places, preferably 
on grass land or on the grasses of ditches and hedges, 
chiefly in late summer and autumn, but in some 
species they may be laid in spring. The grubs live 
for about eight months chiefly on various roots. They 
may however feed above ground at night. In some 
species there are two broods, the first brood of flies 
appearing in the spring and the second in the autumn. 
A large number of the grubs are often found after a wet 
autumn. 
Remedial Measures. 
All wet land should be drained if possible and tufts 
of rank grasses should be kept cut. The grasses of 
hedges and ditches should also be cut and burnt. 
Bush harrowing or rolling pastures when the flies 
are seen in large numbers will kill some of them and 
prevent others from laying eggs. 
Pasture land and leys should be broken up early in 
autumn if possible. A large number of substances 
have been applied to grass land in order to try and kill 
10—2 
