81 
TURN IP. 
Diamond-back Moth. Plutellci crucifer arum, Doubleday ; Cerostoma 
xylostella, Curtis. 
Cerostoma xylostella. 
1, caterpillar; 2, eggs; 3—5, Diamond-back Moth, nat. size and mag. 
The Diamond-back Moth caterpillars have again appeared at some 
of the same localities where they damaged the Turnip leaves in the 
previous season. Notes of their life-history were given in the Report 
for 1883, with a few observations showing that—whether or not nitrate 
of soda or other stimulating dressing carried the plant over attack 
when it was fairly established—it was certain that a weak growth 
threw it under the power of the caterpillar. 
On August 8tli, 1883, it was noted from near York, relatively to 
this attack, “ that there were bad accounts from some farms in the 
district up to a week before,—the Turnip plant had been looking very 
weak from the wet cold weather” ; in 1884, from the reverse (from 
dryness and heat) it is open to supposition that the Turnips were 
checked from this cause, and certain that at Kipling Cote (one of the 
localities reported from) the soil at sowing-time had been in excep¬ 
tionally bad state for the operation (see Turnip Fly, p. 84), 
The only remedies which appear to act are nitrate of soda, or such 
dressings as may drive on growth, and sometimes sweeping the plant 
with boughs fastened on a scuffler, or sending sheep through the field, 
-—in short, the remedies which are used for Nigger or Turnip Sawfly 
caterpillars. It certainly, however, seems as if something might be 
done in the way of 'prevention. The caterpillars spin up both on the 
ground or on their food-plants, whether these are crop-plants or 
common weeds mainly of the Cabbage kind, such as Jack-by-tlie- 
Hedge, Hedge Mustard, &c., and the autumn chrysalids do not change 
to moths till spring. It does not seem at all likely, looking at what 
occurs in regular course of husbandry to Turnip leaves, and to the 
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