6 



The question is a very serious one to all concerned in sugar planting, and whatever step* are taken,, 

 either for eradicating the borer, or keeping it in check, it must be rememberel that success can only be 

 expected from a unity of action among the planting ominunity, and that however careful on? indi- 

 vidual may be to do all that may be directed, his efforts will be unav tiling if he his a neighbour more 

 carelessly disposed, who prefers to allow things to run on in the old groove." 



With regard to the " Kainit" fertilizer, it is hardly applicable to the present case, as the life hist >ry 

 of D saccharalis is well-known, and there is no reason to suppose that at any stage it lives in the soil. 



I have given rather full accounts of various remedies proposed, so that planters may choosy which- 

 ever seem most suitable to their case. There seems to be no doubt, that if energetic means were adopt- 

 ed throughout the infested districts, the pest could be kept well within bounds. 1$ is for ttie planters 

 to consider what measures may best be taken to secure that co operation, without which ndividual 

 efforts will be more or less futile ; but no one can doubt that in these days of severe competition, when 

 sugar is by no means so profitable as formerly, a comparatively small gain or loss, much less than that 

 mentioned by Mr. Van Putten, may make all the difference between success and failure. 



Species Allied to the Sugar-Cane Bokek. 



The genus Diatrwa seems to be more especially neotropical, although a species (D. striata lis, 

 Snell.), very similar to ours, but supposed to be distinct, occurs in the Malay Archipelag ). There 

 are also two species, in addition to D. saccharalis, recognised in the United States, and named by Prof. 

 Fernald D. allcni and D. differentialis. According to Prof. Fernald, as quoted by Comstock (10.) 

 Zeller described several South American species under Diatrwa about the year 1880, but I have not 

 seen the paper in question, and do not find any mention of the species in the Zoological Record." In 

 1882 Zeller described Diatrwa pinosa from Colombia. Chilo, the closely-allied genus to which our 

 insect has frequently been referred, is of very wide distribution, and occurs in both hemispheres. In 

 the United States four species (C. pi ej ad ell as, Zinck., V. densellus, Zell., C. squamulellus, Zell. and C. 

 comptulatalis, Hulst,) are known, and in 1878 Zeller described several from South America 



Diatrcea belongs to the family Crambidce, which consists of moths, usually of plain colours and 

 small size, remarkable for their long palpi, which give them the appearance of having an elongated 

 snout. Several of the species are known to be destructive to plants of the grass family. Two species- 

 of the typical genus, Cr ambus, are known to occur in Jamaica, namely C. curtellus, Walker, and C. 

 ligoncllus, Zeller. 



Other Sugar-Cane Pests. 



It is not proposed to here enumerate the numerous other insects which have been reported to 

 attack the sugar-cane, but as there has been some confusion between the lepidopJerous and coleopterous 

 borers, and between the true borers and other insects, a few remarks seem necessary. 



There is a little beetle of the genus Xy y leb or us, brown in colour, cylindrical in shap3, and Ijss thin 

 an eighth of an inch long, which has caused great alarm in Barbados recently, i:id has been the sub- 

 ject of various telegrams and newspaper notices.* 



Mr. G\ W. Smith (24.) writes on this subject:— 



" The ' Destructive Borer' and the ravages done by that insect to the crop of 1892, is engrossing 



the attention of every one connected with sugar-planting in these islands I have read 



with interest the several letters from the pen of Miss Ormerod published in the Herald newspaper, 

 and have been favoured with a copy of Prof D'Albuquerque's Report 



Three years ago the planters at St. Vincent observed that an insect pest was devastating their 

 canefields, and so severe were its attacks, that it was estimated that one-third of the crop was destroyed 

 by them. 1 had an opportunity of examining numerous samples of diseased canes, and I also spent 

 several days in the field, studying the habits of the insect. At first sight, judging from the numbers 

 of the small beetles (Xyleborus perforans) found in diseased canes, I was led to think that they were 

 the real depredators. On close examination, however, it became clear to me, and numerous subsequent 

 investigations have justified the conclusion ; namely, that the beetle is not the destroyer of the cane, 

 but only a successor to a far more formidable pest — 'the larva of a well-known pest, Diatrwa saccharalis,- 

 and that the beetle very rarely, if ever, attacks a cane that has not previously been ravaged by the 

 motb-borer. This may easily be seen by close inspection, and to note how far this theory heli good, I 

 have repeatedly taken specimens at random from various parts of an affected field, and have always 

 found that in the majority of withered and diseased-looking cane*, there were the large tracks of the 

 moth-borer, without a trace of the beetle ; in a great many instances, there were the tracks of both 

 moth-borer and beetle in the same cane, but never an instance of the beetle aloae. Mr. Grant, the 

 Manager of Woodland's Estate in this island, has been with me at several of these investigations, and 

 after examining numbers of specimens, we are pretty well convinced, so far as it affects Grenada— that 

 not only does the moth-borer first attack the cane, but that the beetle never commences its work until 

 the cane has become thoroughly soured." 



There is no reason to doubt that Mr. Smith's opinion, that the Xyleborus is not responsible for 

 the damage, is a perfectly correct one, and the only amendment needed to his account is that it may, 

 as will appear below, follow the attacks of the weevil as well as the moth. 



The genus Xyleborus includes some species, as X. dispar in Europe aud North America, and X. 

 calatus in North America, which are injurious to trees ; but there are also numerous species which 

 appear to exist only in rotten vegetable matter, or under dead bark. Thus for example, in Insect Life, 

 1890, p. 167, we read of X pnbcscms, which lives in orange and other trees : — 



" The mature beetles burrow in trees of all sorts but have never been known to infest healthy 

 living orange trees, but when found in the orange always occur in the dead or diseased wood. It can- 

 not, therefore, be considered injurious to the orange. The freeze of last winter, which you say killed 

 many of the orange trees, accounts for the presence of numbers of this insect." 



* See also « The Sugar Cane," April 1892, p. 212. 



