MINISTRY OF AGRICULTURE, EGYPT. 



ENTOMOLOGICAL SECTION. 



Bulletin No. 2. 



PRELIMINARY INVESTIGATION 



INTO THE NATURE OF THE DAMAGE DONE BY THE 

 PINK BOLL WORM. 



In the following paper are embodied the results obtained in an 

 enquiry into the nature of the damage done by the Pink Boll Worm. 



The material used was taken from second picking of several 

 varieties of cotton which had been grown in different parts of the 

 Delta. One hundred apparently sound bolls were each time taken, 

 and compared with 100 diseased bolls from the same field. The 

 cotton was taken at the time of picking, in the ordinary way, lint and 

 seed of 100 sound bolls being placed in one envelope, and lint and seed 

 from 100 affected bolls in another. The pickers' instructions were not 

 to take any bolls which would normally be rejected by the harvester, 

 as the object was to ascertain the nature and not the actual amount 

 of damage done to the crop. To ascertain the extent of damage 

 the examination would have to be carried out on other lines. 



On receipt of the samples in the laboratory the total weight 

 of lint and seed together was taken. Then the cotton was ginned 

 and the weight of seed and cotton was taken separately. After this 

 the seed was sorted into sound seed and attacked seed. The attacked 

 seed was only such seed as had been damaged by the Pink Boll Worm. 

 After weighing the sound and attacked seeds separately both lots 

 were counted, 



