THE PESTS AND DISEASES OF THE CANE. 



takes from 1 to 2 minutes; no doubt much longer in boring through the hard 

 epidermis, probably hours. After the hole is completed the beetle walks up and 

 inserts the ovipositor, remaining in this position from 4 to 6 minutes. The bone 

 coloured egg is found embedded parallel to the fibres. It is about 2 mm. long "by 

 | mm. in thickness and slightly bent. The hole close to this is filled in with 

 mucous matter intermixed with particles of fibre. Repeated observations show 

 these eggs hatch in six days. The newly-hatched larva is at first transparent as 

 the eggs of the latter production, the first being of a more opaque colour as also the 

 young larvae, with the head of a darker yellow colour. We found that the young 

 larva went out in the same direction as fibres about one-eighth of an inch deeper, 

 having made a hole one inch long in from four to five hours. As the larva 

 increases in size its power of boring becomes more rapid. A half grown specimen 

 traversed a piece of cane eix inches in length, from one end to the other, in three 

 days." 



Other coleopterous pests of less importance are the ' Bibit Kever,' i.e., 

 cane top beetle (Holanaria picescens), the mature insect of which attacks the 

 eyes of the cane when used as seed, and several ' Leaf Miners ' such as 

 Hispella wakkeri, the larvae of which feed on the cane leaves. 



The well-known and widely distributed ' Shot Borer ' beetle (Xyleborm 

 perforans] perhaps confines its attention to dead and damaged cane and is not 

 to be regarded as a serious pest. 



RhyncotOUS Pests. The Rhyncota are a great order of insects 

 characterized by the development of the mouth parts into an organ known 

 as the beak or rostrum, adapted for the sucking of vegetable and animal 

 juices ; the phases of insect life known as lice, blights, blast, scale and bugs 

 (in its English sense) include many insects of this order. A large number 

 (upwards of twenty in Java alone) have been noted as cane pests. Several 

 historical epidemics of the cane have been due to the Rhyncota, and of these 

 may be instanced that of the Cane Fly (Delphax saccharirora) in the "West 

 Indies in the beginning, that due to the pou-cL-poche-llanche* in Mauritius, 

 about the middle of the nineteenth century, and that in the Hawaiian Islands 

 due to the Leaf Hopper (Perkinsiellia saccharicida) at the beginning of the 

 twentieth century. To these may be added the more recent epidemic of 

 the Frog Hopper (Tomaspis posticata) at present (1909) prevalent in Trinidad. 



Although individually these insects are very small, yet the numbers in 

 which they occur, and the rapidity with which they multiply is the occasion 

 of great damage ; for these same reasons they are indifferent to any but the 

 specialized means of control described below. 



In Fig. 56] is shown a leaf of the cane infected by an aphid (Aphis sacchari) 

 and is illustrative of the great numbers of these, and of allied pests, that may 

 be present in a small space. 



* The true pou-d-poche-blanche is a cpccid (fcerya scychellarum) ; a second coccid ( Pulvinaria 

 iceryi) was also present in the original Mauritius epidemic. The term pou is also applied 

 to a mealy bug (Dactylopius calceolaria) ; this pest has also been confounded with the white 

 louse of Java (Oregma lanigeri) which is however an aphid and entirely distinct. 



t See Frontispiece. 



131 



