OX WARBLE FLY. 
103 
a grey or yellowish head, some small black spots on the ring next the 
head, and two yellow spots on the back of the two succeeding rings. 
The caterpillars feed voraciously, in bad attack clearing away the 
substance of the leaves down to the ribs, and sometimes gnawing away 
these also. When full-fed, they turn to chrysalids in cocoons spun of 
open network on the infested plant, or on the surface of the ground, 
from which the moth comes out in somewhat over or under a fortnight. 
These “Diamond-backs” take their name from the peculiar shape 
of the white or pale markings on the hinder margin of the fore wings. 
When these are folded together, the connected marks form a series of 
diamond-shapes down the middle of the back. The moth is variable 
in general tint, but may be described as more or less brown or greyish. 
The hinder wings are grey or ash-coloured. 
The species is very widely spread; it is stated to extend all over 
Europe, and I have had specimens of the moths and caterpillars, with 
a sample of Cabbage-leaf injured by them forwarded from S. Africa by 
M. de Witt Meulen, of the Winterhoek, Cape Colony. Heavy rains or 
frequent watering of the leaves were noted accompanying as destroying 
many of the grubs, and also that where the Cabbages were planted in 
rows they were protected on each side by a line covered with some 
sticky substance, as molasses. “ Many moths were thereby prevented 
depositing their eggs on the plants.”* This plan (with the alteration 
of substituting any cheap sticky material that would attract the moths, 
for the molasses) might be very serviceable here for garden use. 
Details of the Diamond-back Motli-attack are given in my Reports 
for 1883 and 1884 ; therefore I have not repeated them here, but the 
point of stopping attack in full course by dressings appears worth 
separate mention. 
WARBLES. 
Ox Warble Fly, or Bot Fly. Hypoderma Bovis, DeGeer. 
During the past season the subject of Warble-attack has met with 
steadily increasing attention not only in this country, but also in the 
United States of America; and attention is now being drawn to it, or 
will shortly be so, in Holland; and last year (as well as in each 
successive year since the investigation was especially carried on) the 
reports from cattle-owners, farmers, and others able personally to 
judge of effect of the treatment recommended, confirm the ease with 
which, for all practical purposes, Warble-attack may be got rid of by 
* ‘ Observations on some Injurious Insects of S. Africa,’ by E. A. Ormerod 
(Simpkin & Co., London), p. 47. 
