PROCEEDINGS OF THE SECOND ENTOMOLOGICAL MEETING 109 
In this way on 26th August 1911 the loss percentage in the plots 
selected for experiments was determined and-it was found to be nearly 
25 per cent. On the night of 30th August 1911 at about 10 o’ clock a 
terrible dust-storm moving with a tremendous velocity passed over 
Lyallpur. The houses were shaken to their very foundations and no tree 
was left uninjured in the station. The storm was followed by a heavy 
shower of rain which was recorded as over two inches and a half in the 
town. On the following morning, ¢.e., 31st August, the loss percentage 
in the plots had to be ascertained again, and 1t was found to have fallen 
down to 9 per cent. in one and to 11 per cent. in another. Several 
countings were made but with the same results. This evidently showed 
that the storm accompanied by heavy rain on the night of 30th August 
had some beneficial effect on the standing cotton crop at Lyallpur. 
My detailed observations on this point have convinced me that some 
connection does exist between heavy rainfall and decrease in the number 
of Cotton Bollworms. I shall try to explain now how it happens. 
It is a well known fact that buds, flowers and newly-formed bolls of 
cotton affected by the Bollworms wither and fall off the branches. Ihave 
seen that in case they remain on branches a mere touch of the hand or a 
rough shaking of the branch is sufficient to make them drop to the ground. 
Now when a storm blows over a cotton field on which the standing plants 
bear 25 per cent. damaged buds, flowers and bolls on them, the result 
will be that a major portion of the injured buds and flowers will be 
thrown off the plants. Again, the Bollworms from these fallen buds 
will crawl out and climb on to other healthy plants near which they may 
happen to lie and thus intensify the damage. But matters will be 
different if soon after the storm there should be a heavy rain. If the soil 
is not very pervious water will stand in the field and drown all the fallen 
buds and flowers. The worms inside them will either get suffocated 
and die or get wet and develop some fungus growth which will prove 
fatal to them. Some caterpillars leave the buds and flowers and, being 
unable to get to other plants, die. 
To inquire into this point further, I visited certain places which had 
experienced similar atmospheric variations on the night of 30th August 
1911. Tcalculated the damage due to Bollworm in those localities to be 
between 9 and 10 per cent. There was nothing authentic on record to 
show to what extent the plants were damaged prior to the advent of the 
storm and rain, consequently I had to rely on the results of local enquiry. 
The Zaildars and Lambardars assured me that the loss was much 
greater before than at that time. 
One point more to make my views clear on the subject. The small 
caterpillars on hatching out from the eggs feed (1) inside the cotton 
