﻿XVI 11 



The question that one will now ask is : Are these parasitic 

 and predaceous enemies combined sufficient to prevent any fur- 

 ther serious damage from leaf-hopper? Though a natural one, 

 it is hardly yet a fair question. The leaf-hopper was in num- 

 bers suf^ciently great as to be injurious in 1900, and spread 

 and increased greatl}' since that time. The distribution of im- 

 ported natural enemies began about a year ago. Some of the 

 best of these 'have been distributed much more recently still. 

 To serve fifty or more plantations, many of great acreage and 

 occupying many miles of country, with introduced parasites, 

 must naturally take considerable time. One of our most impor- 

 tant parasites, if it thrives here as in Fiji, as I have already 

 pointed out, is at present hardly to l)e reckoned with. It 

 should be of decided value next year, of much more the )ear 

 after. It is merely a question of natural increase, for that it 

 thrives here at large as well as in captivity is already proven. 

 When one considers the enorm'ous monetary loss, considering 

 the size of these islands, that has been occasioned by the leaf- 

 hopper, I do not think one should cease to seek natural enemies 

 against the pest, until it is absolutely proven a pest no longer, 

 however strong one's hopes may be that the present enemies 

 are sufficient to cope with it. I have been told on the best au- 

 thority and by those most interested, that the loss to these 

 islands caused by the cane leaf-hopper since its first noticeable 

 appearance in 1900 to the present time ma}' be reckoned at mil- 

 lions of dollars, and one is justified in taking every precaution, 

 where so much is at sta'ke. 



ON THE NECESSITY OF FURTHER DISTRIBUTION 

 OF PARASITES IN THE CANE-FIELDS. 



Owing to the manner in which cane is cultivated in these 

 islands, the entomologist working along the lines that have 

 been adopted to control the leaf-hopper pest, meets with a 

 serious obstacle such as is not encountered in dealing with in- 

 sects injurious to our other vegetation. I refer here to the 

 universal custom of burning of¥ 'the trash' over great acreages, 

 after the crop has been harvested. T have been told that on 

 the Colonial Sugar Refining Company's estates in Australia 

 no such burning ofT is allowed. If this is correct, it may help 

 to account for the insignificant numbers of our cane-leaf hop- 

 per there, as well as of several other insects of the same group, 



