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appeared at the same time as boll worm moths from 

 the same consignment of bolls. From boll worms from 

 Kharga Oasis perfect insects of Rhogas have emerged 

 in July and in November, and from those from other 

 localities during October, November, and December. 



Rhogas Kitcheneri has also been bred in the labora- 

 tories of the Ministry of Agriculture from the Kharga 

 Oasis date worm, Ephestia cautella, Walk. This is, how- 

 ever, the only other known host of Rhogas in Egypt. 



Pediculoides ventricosus, Newp., a minute mite, ecto- 

 parasitic on the pink boll worm, on a variety of other 

 Lepidopterous larvae, and even on man, has been found 

 by Mr. Willcocks feeding on common boll worms in his 

 laboratory. He has not, however, found it on this host 

 in the field. 



In addition to the above there are three Hymenopterous 

 insects which are parasitic on the pink boll worm which 

 may in the future attack the common boll worm also, 

 though they have not been found doing so up to the 

 present. These are Pimpla rob orator, Fabr. (family 

 Ichneumonidae), Limnerium interruption, Holmgr. 

 (family Ichneumonidae), and Chelonella sulcata, Nees 

 (family Braconidae). The first of these, Pimpla 

 roborator, is exceedingly abundant on the pink boll worm, 

 and is known, to feed on a large variety of boring larvae. 

 It is highly probable that it may also feed on the common 

 boll worm. The other two species are much less 

 common than the last, though they were far from rare 

 during the autumn of 1913. It is at present early to 

 give any further opinion as to the probabilities, or other- 

 wise, of their parasitizing the common boll worm. 



Investigations with regard to the possibilities of multi- 

 plying the parasites upon the Earias boll worm are 

 occupying the attention of the Entomological Section of 

 the Ministry of Agriculture, the application of insecticides 

 being impracticable in connection with an interior feeding- 

 larva of this description, and reliance having to be almost 

 entirely placed upon the mechanical methods provided 

 for by law. The latter up to the present promise the 

 greatest efficacy. 

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