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TITRNTP. 
land on which the Turnips grew, that any large amount of cocoons 
could remain on the field uninjured. The leaves are destroyed ; if the 
Turnips are fed off on the land the cocoons would quite certainly be 
crushed or smothered, and, if merely ploughed in, it is probably they 
would be killed, their nature being to lie on the surface in the air. 
It seems to me therefore that this attack probably comes from the 
caterpillars on neighbouring wild plants. In 1888 Lord Walsingham 
favoured me with a note of the Diamond-back caterpillars having been 
seen by him in great numbers feeding on the fine-leaved Hedge 
Mustard or Flixweed (Sisymbrium Sophia), and, as this plant is to be 
found on rubbisli-lieaps by roadsides and the like places, “ except in 
the extreme north of Scotland,” it might be well to watch next season 
whether it was one of the weeds of the regularly infested districts. 
On the 19tli of August Mr. W. Tait, of Broomend, near Inverurie, 
N.B., forwarded a package of leaves of Swede-Turnips taken at 
random from a four-acre field at Cricliie (near Inverurie). Mr. Tait 
wrote :— 
“ I did not see a single Turnip, and hardly think I could have seen 
a single leaf, that was not affected more or less like those sent. I saw 
a considerable number of moths. When at rest they seemed of two 
kinds (both Tinea), a few apparently all cream-coloured, but the great 
majority seemed to have a cream-coloured back (or inner margin) with 
the rest of the wings dark brown. [The Diamond-back Moths are 
variable in colour. —Ed.] 
“ I have never seen such a plague before. I ought to have said 
that the margin of the field and a few missed drills are sown with 
yellow Turnip, but they are only slightly affected.” 
The specimens sent me proved to be of Diamond-back Moth, and 
on the 26th of August Mr. Tait, writing further, mentioned he had 
captured some of the moths, and identified them as Diamond-backs 
(by Stainton’s ‘ Mannal.”) He observed :— 
“ I could only lay hands on one larva; they seem all to have spnn 
up on the back of the leaf, but it was too wet to make a very extensive 
search. I have seen several fields during the last day or two in 
different localities all more or less affected ” ; and Mr. Tait noted that 
by report he considered the attack must be yeneral over the north-eastern 
district of Scotland. 
On August 15th Mr. James Thomas forwarded me specimens of 
Diamond-back caterpillars from North Otterington, Northallerton, 
Yorks, with the following note :—“ Up to the 1st of August I had a 
most beautiful prospect of a splendid crop of Swede-Turnips, but 
about that date a kind of blight came upon them, and now the crop of 
ten acres is almost dead. On examining the leaves [a sample of which 
was sent— Ed.] I find they are nearly all perforated to a considerable 
