232 COTTON 



for culinary purposes is little more than a third in heat- 

 ing power. The cost of conversion is of some considera- 

 tion, but should be amply repaid by the diminution of 

 boll worms in the following years' cotton. 



A modification of the existing law in connection with 

 the measures for the prevention -of boll worm propaga- 

 tion is under consideration by the Government, certain 

 important alterations having been made with a view to 

 meeting the situation caused by the advent of a new pest, 

 the pink boll worm (Gelechia gossypielld). If the pro- 

 posals made be adopted and the law be vigorously carried 

 out, great benefit will accrue to the agriculturist in the 

 country, and the quality of the cotton, especially with 

 respect to the later pickings, will be much improved. 



The damage to the cotton crop effected by the Earias 

 boll worm is far in excess of that of any other Egyptian 

 cotton pest. An idea can be got of the probable rate of 

 increase of this pest between January and September in 

 any year by an 'examination of the following figures : 

 2 (i pair) produce 200 eggs, of which 20 insects 



mature. 

 20 (10 pairs) produce 200 eggs per pair = 2,000, of 



which 1,000 mature. 

 1,000 (500 pairs) produce 200 eggs per pair = 100,000, 



of which 50,000 mature. 

 50,000 (25,000 pairs) produce 200 eggs per pair = 



5,000,000, of which 2,500,000 mature. 

 Hence from the one pair, allowing that only 10 per cent, 

 survive in the first generation due to scarcity of food, 

 and that 50 per cent, do so in each of the subsequent 

 three generations, two and a half million boll worms will 

 be produced to destroy the crop in September. This is 

 an indication of what immense good would be effected 

 by a vigorous campaign against this pest at the period 

 when the vitality of the species is at a low ebb and the 

 food supply can be most easily controlled. 



In this paper a selection has been made of three 

 important problems relative to cotton cultivation in 

 Egypt, the first having reference to the possibilities of 

 extension of the planted area and the effect upon the 

 remaining land, and the other two to the influences 



