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screened on the windward side by a strip of heavy white can- 

 vas, to break the force of the wind. All these methods were 

 entirely successful, not only with the Mymarids, but also with 

 tlie more sturdy egg-parasite of the genus Ootetrastickns. 



While the parasites were still comparatively scarce and not 

 easily obtainable in numbers for distribution, they were sent 

 out in colonies, in the glass battery-jars already figured, to such 

 ])lantations as stood in most immediate need. To the various 

 |)lantation agents was left the choice, as to which of their plan- 

 tations should be first supplied. 



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Subsequently as the cane in the experiment station became 

 well stocked with parasites, it was only necessary to take cut- 

 tings of the midribs of cane leaves well filled with eggs and send 

 them to the jjlantations in a very sinii)le form of cage. Prior 

 exi)erimcnts had ])roved that from such leaves parasites would 

 continue to emerge daily for at least two weeks after the cut- 

 lings were made. All that it was necessary for the recipient to 

 do was to hang the cage in a suitable spot, the large number of 

 ])arasites that would emerge from each cage making it almost 

 impossible to fail in establishing them. The emergence of num- 

 bers of individuals day after day rendered the occurrence of un- 

 favorable weather (which is so frequently a cause of failure in 

 establishing beneficial insects, when liberated at one time as 

 adults) a matter of small account. 



