﻿and stocked as aforesaid, at the time the much younger cane of 

 the rest of the field began to be infested with hoppers, would 

 daily be distributing thousands of natural enemies, that should 

 control these. Although such a plan or modification of it might 

 be adopted on some plantations, on others (at least such as are 

 under irrigation) it would either be ditftcult, or altogether im- 

 practicable. Only in the case of some fields of long ratoons 

 would the matter be very simple, when a small area of the 

 original ratoon growth in each field could be left uncut, and if 

 well supplied with hoppers and their natural enemies would 

 serve later on to stock the rest of the field. L'nfortunately. 

 owing, to the fact that ratoons are (exce])t in unusual cases) not 

 severely attacked as comi^ared with ])lant-cane. this matter be- 

 comes one of minor importance. Otherwise, in the majoritv of 

 cases, owing to the clearing of large areas and the burning of 

 traslfT it is probable that new fields will have to be su])])lie(l by 

 cages similar to those al-ready used. Two things will be absu- 

 lutely necessary: (i) that the new fields be well sup])lie(l with 

 l)arasites ; (2) that they be stocked immediately the ho])])ers en- 

 ter them and commence la\ing. This ])lan, though less satis- 

 tactory than would be the other method, is nevertheless simple, 

 and does not call for much expenditure of time, uov for skilled 

 labour. The one thing necessary to be i)ositively ascertained is 

 that the s|)ot whence the cuttings for distribution are taken is 

 well supplied with all the kinds of i)arasites that it is desired to 

 establish in new tields. It is ncnv well known to us that (/// these 

 destroyers are not yet established /// all f^.irfs of all plantations, 

 and therefore at ])resent unless an entomologist ])reviousl\- 

 test samples from the spot, whence distribution is to l)e 

 made, it is quite likely that some of the most valuable parasites 

 will not be taken to the new fields. If a sample be submitted 

 to the entomologists, it can be passed as fit to supply all neces- 

 sary parasites to new fields, or if not, cages of the deficient 

 species can alwa}'s be supplied from the cane in the grounds of 

 the Experiment Station in Honolulu. As the parasites are con- 

 tinually spreading and increasing, such expert examination will 

 at the most be necessary for a year or two : for it is perfectly 

 certain that by that time all the species will be so general that 

 it will be (|nite im])Ossible to take any extensive sample of cane- 

 leaves that l)ear eggs of leaf-hopper, which will not contain all. 

 Such in fact is now the case in the cane at the Experiment Sta- 

 tion. To sum up, the clearing of all can^ from large acreages 

 is a decided obstacle to the complete success of natural enemies 



