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which comprehend the distribution of the ceca, their various relations 
to the bodies of the species possessing them, and the kinds and nature 
of the bacteria constantly harbored by them. The discovery is one of 
great interest and may become of importance. We hope that Prof. 
Forbes will not confine himself to the Hemiptera in his investigations, 
but will also follow the organs in other orders of insects which have been 
similarly assumed to have pancreatic functions such as the ramified 
appendages of the stomach in Gryllotalpa. 
Plutella cruciferarum in England.—The English Board of Agriculture 
has just published aspecial report of the Intelligence Department, by Mr. 
Charles Whitehead, on an attack of the Diamond-back Moth Caterpillar. 
Mr. Whitehead has given in this report a full account of the damage done 
by this insect during 1891 in various districts in England, to which we 
have already referred on page 8lof Vol. tv. The author gives descrip- 
tions of the different stages of the insect, an account of previous attacks 
by the same species in Great Britain, a general review of its distribu- 
tion, and some account of the presence of the species in foreign coun- 
tries, in which, curiously enough, he makes no mention of its eccur- 
rence in New Zealand or the United States. Under the heading “ Ex- 
tent and nature of the injuries and losses to crops” a most deplorable 
state of affairs is indicated, in some cases the loss on the Turnip and 
Swede crop reaching 60 per cent. The season seems to have been a 
favorable one for the development of Tineina of many species, and in 
a number of cases the severity of the present season’s attack by the 
Plutella has been directly traced to carelessness in allowing the growth 
of Wild Mustard, Charlock, Shepherd’s Purse, and other Cruciferous 
weeds in the vicinity of the fields the previous fall. 
The damage was mainly done in the vicinity of the seacoast, where 
wild Cruciferous plants grow in great abundance. The dry weather, so 
marked in the early part of the season of 1891, also aided in the rapid 
development of the insect. A number of remedies were tried by farmers, 
and Mr. Whitehead summarizes these in his general conclusions. A 
mixture of soot in lime was shown to be the best remedy tried. Paraffin 
(kerosene), quassia, and carbolic acid solutions are said to have been 
‘‘ efficacious to some extent.” Brushing off the caterpillars by means 
of boughs fastened to horse hoes (cultivators) proved to be a good prac- 
tice, especially where the hoes were followed by other hoes or * scufflers” 
to bury or kill the caterpillars. Mr. Whitehead finally advises cutting 
down the Cruciferous weeds in the spring, as they may serve as breeding 
places for the first brood of the insect, but he is of the opinion that the 
unpropitious weather of the latter part of the season and the hosts of 
parasites which have been developed will have reduced the insect to 
such a point that next year will show but slight damage. Among natural 
enemies Limneria gracilis and L. tibialis were noted. Of these LZ. gracilis . 
greatly predominated. 
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