nmCEFDlNGS OF THE THIRD ENTOMOLOGICAL MEETING 509 



In August 1917, the law was modified in order to permit the pulling 

 up of sticks before removal of bolls in all cases in which it appeared 

 advisable to the Ministry to permit this course of action. This was 

 because it had been demonstrated by various Inspectors of the Ministry, 

 and by members of the public, that it was possible to do the work of 

 boll-pulling more efficiently, at less cost and with less spilling of bolls, 

 if the trees could be pulled up and combed through rakes or put through 

 a specially designed machine. This modifying law (No. 12 of 1917) 

 marks a real advance in the development of the campaign. 



On account of the fuel shortage a modifying law (No. 11 of 1918) 

 has had to be passed permitting the Government to seize and confiscate 

 cotton-sticks instead of seizing and burning. 



Having detailed the progress of legislation and outlined the lines 

 of growth of the Pink Bollworm campaign, a few remarks on the theories 

 underlying them may yet be made. 



The Campaign in all its aspects, fieldwork, seed treatment in the 

 ginneries, and screening of seed- stores, aims only at the elimination of 

 the long-cycle larvse or of the moths belonging to the long-cycle genera- 

 tion. Short-cycle moths emerging at the end of the season are com- 

 paratively innocuous as compared to their long-cycle progeny. Now 

 it has long been known to us that the proportion of long-cycle larvae 

 in the Pink Bollworm population is constantly increasing as the season 

 progresses. Recent work has shown that even in the summer months 

 there are amongst the short-cycle larvse a few per mille of long-cycle 

 worms. From breeding results of 1917-1918, we find that green bolls 

 collected before 10th October contained 5 per cent, long-cycle larvse 

 and 95 per cent, short-cycle. After this date the proportion changed 

 rapidly. For the whole period Uth October to the end of November 

 there were 23 per cent, long-cycle larvse. But for the last three weeks 

 of November all the worms give rise to long-cycle moths. 



It will be seen that, supposing it were possible to take the crop early 

 enough every year, there would be very few long- cycle larvse to carry 

 over to the next year, and consequently the subsequent years would 

 know less and less of the pest. The longer the delay the more serious 

 the menace for the future. Every week thousands of attacked bolls 

 fall off the trees and escape from later control by being trampled into 

 the ground, by falling down cracks in the earth, or by being silted 

 over when the land is watered. The later in the season the more 

 certain it.is that such bolls must contain resting larvse. Without doubt 

 many of these larvse are destroyed by ants, by disease or parasites, 

 by being buried too deeply or by exposure to the sun. But immense 

 numbers manage to survive through to the next season and even to 



