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8. The rind-fungus appeared, in some cases at any rate, to have de- 

 veloped, not from the disease in the roots, but from the infection in the 

 top, for the joints in the lower part of these canes seemed to be of the 

 normal length and not stunted. 



9. The appearance of the rind-fungus is well-marked and charac- 

 teristic. Minute punctures are seen in the rind of the cane, filled with 

 a sooty-black stuff which eventually protrudes and becomes dry and 

 hard. A very small portion of this black stuff rubbed up in water and 

 examined under the microscope shows that it is composed of spores. 

 The exceeding smallness and lightness of the spores allow them to be 

 carried by every breath of wind, and in this way one diseased cane is 

 quite sufficient to infect a whole estate. From experiments made at 

 Kew, it appears that these spores are able to germinate on, and attack, 

 the tender cane-top, but wherever either the moth-borer or the shot- 

 borer exists, the tunnels they make from the outside all through the 

 cane, give ready access to the spores, and this constitutes their peculiar 

 danger wherever the fungus-disease exists. When a spore germinates, 

 it gives rise to long thread-like growths which penetrate the tissue of 

 the cane and fill up the cells, feeding on the sap, and so preventing 

 proper growth. Eventually these threads form spores again in nu- 

 merous spots which burst through the rind and multiply the chances 

 of disease by many million-fold. 



10. The root disease seems to be propagated in the first instance by 

 planting tops of canes already diseased with the rind-fungus. Its dan- 

 ger is in the infection of the soil where the plant is growing, for it 

 forms peculiar spores, called " resting- spores," which remain in the 

 ground for an indefinite period, resisting decay. As soon, however, as 

 the growing rootlet of a cane comes in contact with them, they ger- 

 minate and penetrate the root. It is not known how long these resting 

 spores can remain in fallow ground without decaying, but probably for 

 years. 



11. A nematode worm was noticed in a minute portion of soil at- 

 tached to a rootlet. These worms and the root-disease may mutually 

 assist one another. 



12. The Bourbon Cane which had for years given large crops in 

 Cave Valley will soon be exterminated there by the disease, while the 

 Black Cane is not attacked. This circumstance points to some cause 

 or causes, antecedent to the fungus, affecting the Bourbon and not the 

 Black Cane. The Bourbon has been the " Cane of the Valley" for 

 many years, and its weakness of constitution which leaves it liable to 

 the attacks of the fungus, may be due to exhaustion of some of the con- 

 stituents of the soil necessary for plant food, or to the planting of weak 

 tops, or to planting the same canes over and over again on the same 

 estate. 



13. It is a difficult matter always to suggest remedies, for, though 

 they may be effectual on a small scale, it may be quite out of the ques- 

 tion to apply them on a large scale for various reasons, such as expense, 

 or want of labour. But it is still more difficult to advise, when the 

 causes are complicated, and all the data — for instance, analysis of soil — 

 necessary for a decided opinion are not before us. However, from the 

 consideration of such facts as have been stated, it is obvious that certain 



