OF INJURIOUS INSECTS. 
43 
centre. The flies are sprinkled with black bristly hairs, and the legs 
are also bristly. The larva or maggot is about one-third of an inch 
long, white or tinted with greenish, somewhat pointed at the head, and 
blunt at the tail; it is legless, and resembles the larva of the Celery- 
leaf miner. Like it, the maggot of the Beet Fly feeds between the two 
sides of the leaf, gnawing away the cellular tissue, and thus reducing 
the part of the leaf attacked to a mere empty blister. Mr. Norgate 
noted larvae as abundant in the Mangold leaves at Sparliam on the 
20th of June. On the 1st of July Mr. Norgate dug round some of 
the attacked Mangolds, and found the pupae (to which the larvae had 
turned) about three inches below the surface of the ground. “ One 
held of nineteen or twenty acres was considered to be set back about 
three weeks by the injury to the leafage.” From these pupae, Beet-flies 
hatched on the 7th and on the 13th of July, and on the 1st of August 
Mr. Norgate captured many of the flies at rest on the Mangold leaves, 
and found a large number of eggs on the under surface of the leaves. 
The larvae appeared now more numerous than before, and the whole 
field looked brown with the dry and blistered leaves ; and on the 29tli 
of September Mangolds at Sparliam are noticed as “fresh blown ” by 
the flies. Mr. Norgate’s observations thus show certainly two broods, 
and probably three, in the course of the season, and also, as he found 
the pupae in the earth, and no specimens that he observed turned to 
the pupal state in the leaf, it points to the class of remedies needed to 
get rid of them. 
The Beet Fly has not been much observed in previous years, but 
in the present season injuries to the Mangold crops have been reported 
as more or less prevalent over the country (from the East to the West 
of England, and as far north as the neighbourhood of Dumfries, and 
also in the West of Ireland), which have either certainly been caused 
by the maggot of this Fly, or may reasonably be attributed to it. 
Mr. Service mentions dipterous larvae as mining in the leaves of a field 
of Mangolds at Slogarie, and doing much damage. 
Mr. Fitton, writing from Clieerbrook Nantwicli, Cheshire, reports 
that, in the case of a Grub destroying the leaves of the Mangolds (in 
its method of working similar to that of the Celery Flv), different 
