218 



THE AGRICULTURAL NEWS. 



July 6, 1912. 



INSECT NOTES. 



ECONOMIC ENTOMOLOGY IN FIJI. 



The ] )epartment of Agriculture, Fiji, has recently pub- 

 lished a report on Economic Entomology, by Frank P. 

 Jepson, B.A. (Cantab.), F.E.S., Government Entomologist. 



Mr. Jepson assumed the duties of his office in October 

 1909, and his report has for its primary object a statement 

 «f the manner in which his time was spent during the first 

 year of his appointment. 



The report is of very considerable interest, both because 

 of the fact that it includes an account of the first work in 

 Fiji by a Government Entomologist, and also on account of 

 the very large amount of information that it contains. 



Fifj. 5. Grub of West Indian Sugak-cane 

 Weevil Boeee. 



In the introduction, which includes a general summary 

 of the work of the year, the author discusses, among other 

 topics, the necessity for the inspection of imported fruit and 

 jjlants. It is stated that in all probability the insect enemies 

 •of cultivated crops in Fiji have with few exceptions, been 

 introduced from other countries, arid the great need for 

 I)roper inspection of all imported plants is strongly brought 

 out. Several insect pests are named which are not at the 

 present time known to occur in Fiji; the introduction of 

 these would seriously affect the agricultural prosperity of the 

 Colony, while the probability of such introduction is very 

 great, unless adequate means are taken to prevent it. 



One instance is given in particular to illustrate this 

 point. The rhinoceros beetle (Ovi/ctes rhinoceros, L.) has 

 recently been introduced into Samoa from Ceylon. It is 

 believed that this insect was transported in packages contain- 

 ing rubber seeds. This is a very serious pest of coco-nuts 

 and many acres of full-bearing coconut palms have already 

 been destroyed, and as there is no satisfactory manner of 

 dealing with this pest, its importance seems likely to increase 

 rather than to diminish. 



The use of natural enemies is also discussed in the 

 report, and the value of combating insect pests by this means 

 is clearly shown. 



The section on Anhropoda Injurious to Man and Animals 

 contains accounts of mosquitoes, ticks, lice and related insects 

 which in general are similar to those known in the West 

 Indies, and the same remark applies to the insects mentioned 

 in the sections entitled Insects Injurious to Stored Goods, 

 und InsectS InJLaious_to Timber. 



The insects dealt with in this report which seem likely t* 

 be of greatest interest to the readers of the Ai/ricultural A'eicrs- 

 are certain of those mentioned in the chapter entitled Insect* 

 Injurious to Cultivated Crops. 



Several insects are regarded as pests of coco-nuts. Oi>e- 

 ■of these is a sm-ill moth, Levuana iridescens. The larva of 

 this insect feeds upon the leaves of the coco-nut palm, eating 

 from the under surface, and in cases of severe attack destroy- 

 ing the entire tissue of the leaf except the upper epidermis. 

 The attacked areas are in the form of narrow lines running: 

 lengthwise of the leaflet, and it often occurs that a number of 

 these lines, each the work of a separate larva, may be founct 

 in a leaf. 



The pupa of this insect is generally formed in the- 

 fibrous mass at the bases of the leaves. This habit, together 

 with the fact that the mass of loose fibre in the axils of the 

 leaves afl'ords a shelter for many insects and other animal^ 

 suggests the desirability of clearing it awa)', in dealing with 

 infested trees. This, however, involves a large amount of 

 labour, which renders it impossible on many coco-nut planta- 

 tions. Spraying is not feasible, often on account of the 

 lack of a sufficient supply of water. It is suggested therefore 

 that the natural enemies of this pest should be sought for iij. 

 places where the latter is likely to be indigenous. 



The coco-nut leaf miner {Prointcotlieni reichei) occurs on 

 certain islands in the Colony, causing a considerable amount 

 of danger on small areas. Trees which are attacked are 

 conspicuous on account of the large brown patches upon the 

 leaflets. These patche.'i are the dead areas resulting from 

 the feeding of the beetle larvae, which eat out the green 

 portion of the leaf, leaving the drj' upper and lower epider- 

 mis. This pest is largely controlled by a minute hymenop- 

 terous parasite. 



Coco-nuts are also attacked in Fiji by certain stick 

 insects, closely related to the guava lobster {Diuplierudes- 

 f/iffaii.fea) and the common god. horse (P/ianocles spp. ) of the 

 West Indies. 



The flowering spathes of the coco-nut are often attacked 

 by the boring larvae of moths and beetles, and the cabbage, 

 or bud, is attacked and destroyed by the larvae of a smalt 

 moth, Trac/ij/centra sp. 



Fiii. 6. West Indian Sugar-cane Weevil Boeee. 



The attack of this latter insect produces a conditioB 

 which Mr. Jepson states closely resembles that which results 

 from an attack of bud rot in the West Indies. 



The only scale insect mentioned as attacking coco-nuts 

 in Fiji is the coco-nut scale (Pseudococcus j'andani). This 

 insect appears to be fairly well controlled by a small lady- 

 liird beetle, Aiiisercus affinis. 



Bananas are reported as being attacked by several insect 

 pests, the chief of which is the banana borer, Spkenophorus- 

 sordidiis. This insect, which has occurred in limited num- 



