The Bianiond-hacli Moth. 
621 
" Every bfeliefit to be derived from heavy rains ; in fact, I much 
question whether the pest could be entirely destroyed by any arti- 
ficial means without them." — G. T. 
" Caterpillars appeared dui-ing very dry weather, which was 
followed by very heavy rains and thunder-showers, but they had no 
eflfect on caterpillars, which, in fact, did most harm during, and 
immediately after, rains." — F. W. 
" Heavy showers undoubtedly have done good." — T. H. W. 
Summary. — -With only two exceptions, the above observation.? 
concur in the beneficial ell'ect of rain in checking the caterpillar 
attack, especially when accompanied by a drop in the temperature, 
and by high winds. A large part of the good done is presumably 
by the moisture in the air and at the roots helping on growth, but 
the winds and chillier weather would be directly injurious in 
some degree to the caterpillars. 
Cold rains in warm weather have been known in some cases to 
be rapidly destructive to caterpillars, by causing a flux which soon 
reduced them to empty skins, and the following few words with 
which I have been favoured from Mr. Thos. Fraser point so forcibly 
to something of this kind havinsc occurred to the diamond-back 
caterpillars under his observation that I give his remarks sepa- 
rately. 
Mr. Fraser, writing from Ardfin, Island of Jura, by Green- 
ock, N.B., on August 21, mentioned : "I observe that the moth 
is decaying or dying in the flrst stage now ; no doubt the result of 
the heavy rain we had recently." 
4. Nature of land, how cultivated, and what manure loas used. 
" At Thornham the soil is fairly good, bright, and light, with 
chalk about two feet below. Land ploughed about three inches, 
difficult to plough deeper thei-e ; no manure used." — E. A. A. 
"In some cases whole fields were destroyed ; in other cases por- 
tions of a field seemed to escape with comparatively little damage. 
" On inquiry into the reason of this, it was at once apparent that 
it depended to a great extent on the nature and condition of the 
soil, and the state of plant-growth at which attack commenced. 
" Early-sown turnips in good soil, both as regards mechanical 
and manurial condition, survived the attack and continued to grow, 
while on hard clay soils, and on back lying soils trending to the 
north, and where the attack had commenced shoi-tly after or during 
thinning, the plants were entirely eaten up. 
"Tliere is no doubt that the best preventive is to have the land 
in high-class condition. In a field, for example, which was well 
done to, a portion which got an extra dressing, from the more 
vigorous growth of the plant, seemed almost to have escaped." — A. B. 
" The land is alluvial deposit and sand. I farmed part of the old 
bed of Loch Leven. It was five years in grass, oats last year, and 
was ploughed in December rather wet, and not trenched again till 
June 1. 
