SNOWY FLY. 
11 
The Aleyrodes, or “ Snowy Flies,” are nearly allied to the Aphides 
and Scale insects, and, like them, injure the plants they attack by 
piercing into them with their suckers and drawing away the juices. 
The common “Cabbage Snowy Fly” (figured above) lays its eggs in 
patches, and the young, which hatch in somewhat less than a fort¬ 
night, spread themselves over the leaves, and there feed (looking like 
minute white or yellowish Scale insects) for about ten days ; they then 
turn to chrysalids on the skin of the leaf, from which the little four¬ 
winged flies come out in about four days more. This is the sequence 
given by John Curtis of their summer life, but the insects live and 
multiply throughout the year. I have seen them in great numbers on 
Cabbage plants in W. Gloucestershire, and they occasionally appear as 
a regular pest, as in 1846, when “the whole of the Broccoli and 
Cabbages in the neighbourhood of Romford, Essex,” were reported to 
be infested by millions of Aleyrodes in the fly-state. 
The attack, when bad, ruins much of the leafage, which turns 
brown or yellow, and falls off; and there is the unusual inconvenience 
that the creatures are to he found doing mischief all the year through. 
They have been observed to withstand rain and cold, and have been 
found in all stages in the middle of the winter. 
There is no difficulty in recognising this attack, first by the little 
white or brownish scale-like grubs ; next by the singular appearance of 
the little flies which rise on the plants being disturbed, as I have seen 
them when a dog has run amongst the Cabbages, as if a shower of 
small snowflakes w T as dispersed through the air, the “ Snowy Flies ” 
immediately settling down again. 
As the attack is mainly beneath the foliage, there is great difficulty 
in bringing any kind of dressing to bear on the insects ; and the best 
treatment appears to be cutting off the infested Cabbage leaves and 
destroying them. This should be thoroughly done, and at once, as, if 
the leaves are only thrown to a rubbish-heap, they will remain fresh 
enough for some days to support many of the grubs up to the stage in 
which they turn to the chrysalis. Throwing the leaves to be trampled 
in farm-manure gets rid of them thoroughly, or burning amongst 
rubbish would answer better. 
The “ Snowy Flies ” shelter in any convenient nooks on the surface 
of the ground, or under leaves; therefore, digging infested ground or 
top-dressing with caustic lime would be of service. 
