43 COTTON 



India to investigate the methods of suppressing the 

 Earias boll worm in that country, and on the return of 

 this officer a number of larvae infected with Rhogas 

 Lefroyi, Dudgeon and Gough, were introduced. 



The introduction of these was, however, rendered 

 unnecessary owing to the discovery a little later of an 

 already acclimatized nearly allied insect, which has been 

 described under the name of Rhogas Kitcheneri. 11 



The first recorded specimens of R. Kitcheneri were 

 bred in October, 1912, in the laboratories of the 

 then Department of Agriculture, from common boll 

 worms from Beni Souef. The species has since been 

 recorded from Menufia and Kharga Oasis. Further 

 investigations will probably show that it occurs through- 

 out the greater part, if not the whole of Egypt. How- 

 ever, although it was abundant in consignments of boll 

 worms received from Beni Souef and Kharga Oasis, it 

 does not seem to be generally common in the Delta. 



Although the act of oviposition has not been actually 

 observed in this species, the eggs are probably laid in 

 the boll worms when they are entering or leaving a boll, 

 or when they are near the entrances of their tunnels. As 

 the ovipositor is only 5 mm. long, Rhogas cannot lay 

 its eggs in larvae which have made their way well into 

 the bolls, as can Pimpla roborator, the commonest para- 

 site of the pink boll worm, which has a much longer 

 ovipositor. One egg only is laid in each boll worm. 

 The young larva lives inside the host, feeding at first 

 only on the less vital tissues, such as the fat bodies. So 

 skilfully does it avoid the vital organs that it is not until 

 the Rhogas larva) is full grown and has left its host that 

 the latter dies. After leaving the host the larva pupates 

 in a small ovoid silken; cocoon, which is generally found 

 beside the remains of the dead boll worm. 



Nothing is known of the number of generations of 

 Rhogas that take place in the course of a year, but it 

 is probable that the life-history closely approximates to 

 that of the host, as all the specimens that have been bred 



11 Dudgeon and Gough. Bull. Ent. Soc. Egypt _, 1912, 

 pp. 140-141. 



