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practice in other sugar-growing countries. In the United States there- 

 is a winter, the moth-borer hibernating as a grub in the cane ; and the 

 burning of the stubble and the dead canes will probably be of service. 

 In Mauritius the moth-borer is credited with spinning a loose cocoon in 

 the trash, and burning the trash will probably be very effective in des- 

 troying it. This is quite sufficient to determine the Mauritius borer 

 as different from ours. I have not at present met with any stage of our 

 borer in the trash ; it changes from the grub to moth in the furrows 

 in the cane. 



" I recommend a study of parasites of the moth-borer. At present a 

 fungus, attacking it in its burrows, does us good service. In one case I 

 detected 13 dead grubs in three Caledonian Queen canes. These were all 

 victims of an undetermined fungus which 1 mummifies' the grubs. 



" I have not at present succeeded in obtaining the ripe spores for 

 trials in inoculation. 



" I have evidence that the vast majority of moth-borer eggs are 

 destroyed by a small parasitic fly. Some of the eggs turn yellow and 

 addled ; these probably were unfertilised. Others are left transparent 

 and empty ; from these the grubs have escaped. The great majority, 

 perhaps great because of their conspicuousness. turn black, and when 

 punctured show a much smaller and more regular hole than the minute 

 grub makes. These I regarded as parasitised. I laid the suspected 

 specimens of blackened eggs before Mr. Hubbard, the entomologist in 

 the United States Department of Agriculture, who is now visiting 

 Montserrat, and he at once recognised the presence of a parasite 

 belonging to a well-known class of egg-eaters. 'When I detailed the 

 numbers of eggs laid by the moth-borer, and the great majority of 

 blackened ones, he remarked, ' Without this fly you could not grow a 

 * cane in these islands/ " 



The following papers are published in continuation of previous cor- 

 respondence : — 



Royal Gardens, Kew, to Colonial Office. 



Eoyal Gardens, Kew June 5th, 1894. 



Sir, 



I *have the honour to acknowledge the receipt of your letter with 

 enclosures of May 8th and June 2nd on the subject of the disease now 

 affecting the sugar-cane in the West Indies. 



2. The history of the matter is briefly this : — 



In a letter to the Colonial Office, April 5th, 1893, I pointed out the 

 appearance of the disease in the TTest Indies, now generally spoken of 

 as " Rind-disease." I stated that it was due to a fungus to which the 

 name Trichosphceria has been given ; that the fungus possessed differ- 

 ent reproductive phases which had been mistaken for distinct fungi ; 

 that it was a very destructive parasite which can effect a lodgment on 

 the young leaves of the sugar-cane but not on the old ones ; and finally, 

 that no practical remedy can be suggested to check the progress of the 

 disease beyond the "cutting out" and the careful destruction by burn- 

 ing of every diseased cane. In a further letter, of March 12th last, I 

 stated iny opinion that the Trichosphceria had made its appearance 

 quite recently in the "West Indies, and I had little doubt that it had 

 been introduced from the Old World. 



In another letter of November 3rd, 1893, I informed the Colonial- 



