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It is coniinonly asserted that this disease of the sugar-cane 

 receives its common name on account of the fact that its pres- 

 ence in the tissues of the cane gives rise to an odor resembhng that 

 of pineapple. The specific name of the fungus, ethaceticus, refers 

 to the same fact, its translation into English reading, "acetic 

 ether," so that we may call the species the acetic-ether-producing 

 fungus. 



It is true, that, in some of its stages, and especially in some 

 varieties of cane, the growth of the fungus gives rise to an odor 

 reminiscent of ripe pineapple, but a delicate nostril would sel- 

 dom, I think, mistake one odor for the other. More often the 

 odor is that whicii we associate with fermenting fruit juice, 

 due no doubt to a mixture of the vapors of various alcohols, 

 acids, and ethers, prominent among which may be, and prob- 

 ably is, acetic ether. This odor of fermentation is the usual 

 characteristic of most of the stages of the pineapple fungus as 

 it occurs in cane. Only the later stages of the fungus attack 

 are devoid of this odor, or if present, it is overpowered by others. 



There is another reason why the name pineapple disease may 

 be applied to this malady of cane, and that is that the same, 

 disease attacks the pineapple, as well as some other fruits. 

 This fungus is, in fact, one of the serious diseases of the pine- 

 apple in some places. It is prevalent in the Hawaiian Islands 

 on pineapples and does no small damage on some plantations. 



The fact that tlie disease can be present in a most pro- 

 nounced form without the odor of pineapple being noticeable 

 renders the name a little unfortunate from the first point of 

 view, but nothing can be said against the name from the 

 second point of view, that is to say in view of the fact that the 

 disease also attacks the pineapple. It is well to know that 

 in fields where the disease is common one may often dig up 

 and examine scores of cuttings without once detecting a pro- 

 nounced odor of pineapple. As before stated, the variety of 

 cane is one factor in the production of this odor. Yellow- 

 Caledonia is one of the varieties that even \\hen suffering acutely 

 usually gives off merely an odor of fermentation. I have found 

 the ethereal odor most pronounced in such varieties as the Striped 

 Singapore, and in such canes the odor is sometimes much stronger 

 than that of the most highly scented pineapple. 



HOW TO DETECT PINEAPPLE DISEASE. 



To detect this disease in planted cuttings one has therefore to 

 rely upon other indications than the odor of the diseased tissues. 

 The odor is usualy present in a faint degree, and is certainly 

 quite different from that of sour cane. As a rule it is a very 

 faintly etherial odor that almost evades detection and is rather 

 earthv and clean in character. 



