450 PROCEEDINGS OF THE THtRD ENTOMOLOGICAL MEETING 



regularly. No doubt along with this simjDle measure, other measures 

 will have to be adopted concurrently to produce the desired result. The 

 introduction of parasites will still require to be done. But much reUance 

 carm.ot be placed on this parasite work, unless it is done by specially 

 trained men. This work is rather technical and as such caimot be 

 trusted to an agency, such as the cultivators, to adopt and carry it 

 through. The parasites, though effective as checks to Bollworms to 

 some extent, cannot be expected to bring about the desired change 

 soon, unless a parasite is found which breeds fast and lays a large 

 number of eggs. None of the Bollworm parasites known up to this 

 time fulfils these conditions, Microbracon lefroyi no doubt parasitizes 

 Earias as well as the Pink Bollworm {Platyedra gossypiella) to some 

 extent, but does not seem to be the ideal parasite so far as our investi- 

 gations at Pusa appear to indicate. Being a Braconid it lays only 11 

 to 13 eggs on its host — the maximum number of eggs found laid by M. 

 lefroyi in the Punjab is said to be 21 — and, as these grubs develop a 

 tendency to cannibalism in confinement, it is possible that even this 

 small number of, grubs does not develop on the host. Thus it is not 

 able to keep pace with the development of its host and as such 

 is not very effective in circumventing its further increase. We have 

 worked at the question of parasitization for some years past, and 

 have come to the conclusion that Chalcidid parasites are more effective 

 than either Braconids or Ichneumonids. Hitherto we have not 

 found any Chalcidid parasite which can be said to be effective against 

 the Bollworms. The one Chalcidid parasite that has been found is on 

 th^ pupae and is not very effective. Hitherto we have not found" any 

 parasite on the eggs and none s\xch has been recorded from other cotton- 

 growing countries where Earias occurs, and this is because of the way 

 the eggs are laid on the host-plants. The eggs are laid singly and are 

 coloured cryptically. It is perhaps due to some such cause that the eggs 

 enjoy complete immunity against parasites. 



Earias fabia and E. insidana are found at Pusa in cotton. Hibiscus 

 esculenius, H. abelmoschus, H. Sabdarijfa, H. panduriformis, H. rosa- 

 sinensis, H. cannabinus, Abuiilon indicum, and Althcea rosea. They have 

 not yet been found in Hibiscus vitifolius, H. mtttabilis, H. triciispis or 

 Malacha capitata, although these plants have been examined from 

 time to time. It is only in Hibiscus abelmoschus that we have been able 

 to find all the three species of Earias, E. fabia, E. insulana and cupreovi- 

 ridis, feeding on the same plant. E. cupreoviridis attacks jute capsules 

 also and has not been found in cotton. Earias insulana is found more 

 frequently in Abutilon indkum than in either cotton or H. esculentus 

 at Pusa. The larvae of all the three species of Bollworms have been 



