It is unfortunate, to say the least, that the matter of the cause of 

 the rind disease should be further involved by confusing the symp- 

 toms. Howard is here dealing with an entirely different fungus and 

 entirely different symptoms from those which characterize the rind 

 disease. 



As has been shown neither Howard nor Massee nor any other 

 worker succeeded in getting good pure culture inoculations of Melan- 

 conium sacchari. On the other hand, no one has found any other 

 fungus than Melanconium sacchari associated with the typical con- 

 ditions of the disease, i. e., the eruptions of the rind. Until more 

 is done, therefore, to prove the contrary, Melanconium sacchari should 

 be considered as the cause of the rind disease. 



NATURAL INFECTION OF STALK, LEAVES AND CUTTINGS. 



Whatever question there may be about the active parasitism of 

 the rind fungus, there can be no question as to the actual occurrence 

 of the fungus on the cane in the field. The following is in part a 

 repetition of what has gone before, but taken altogether it will serve 

 to summarize the conditions. 



OCCURRENCE ON THE STALKS. 



Melanconium sacchari commonly occurs on green cane stalks at 

 such points of injury as those caused by the weevil borer, near the 

 base of the stalk. These injuries are not sufficient to kill the stalk 

 and it remains green until infected by the rind fungus, and even 

 then the infection progresses only according to the vigor of the cane. 

 The fungus occurs at similar points of injury caused by the moth 

 stalk-borer which may occur any where along the stalk, perhaps more 

 commonly near the top. The moth borer or some bud moth often 

 gets into the top of the cane and kills the heart. This injury is 

 usually succeeded by an infection of the rind fungus which pro- 

 gresses downward. Occasionally the top is rotted and a Melanconium 

 infection is present without any sign of insect injury. The extent 

 of all this damage depends largely upon the vigor of the cane as 

 discussed elsewhere. 



OCCURRENCE ON LEAVES. 



A point that apparently has not been considered of great impor- 

 tance is the occurrence of this fungnis at the base of leaf-sheaths 

 and occasionally near tlie joint of the sheath and blade. This occur- 

 rence is very common in cane over 8 or 10 months old. It has not 

 been proven to be the same as the stalk fungus, but it cannot be 



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