panying the cankers, but there is a shrinking of the internodes and 

 a general condition of pithiness and lack of juice. All cankered 

 canes show mottling of the leaves, but the reverse is not true. 



It may be noted at this point that not only is there a lack of 

 .juice in cankered canes, but what does occur is of an objectionable 

 nature from the mill stand point. A very high glucose ratio is 

 reported (non-crystallizing sugars) and the juice behaves badly dur- 

 ing clarifying and other processes to which it is subjected. A com- 

 prehensive series of chemical tests is about to be made at this Station, 

 to be reported upon later. 



Causes. — No definite cause lias as yet been found although many 

 have been suggested. The juice of diseased stalks has not been found 

 to be infectious. No fungi have been found in connection with it 

 which could reproduce the trouble. It has been found that apparently 

 normal seed pieces from stalks showing mottling, even after disinfec- 

 tion and planting in sterile soil, produced mottled shoots. 



The entire question of degeneration or running out of varieties, 

 together with the effect of abnormal weather conditions and exceed- 

 ingly poor agricultural practices have been studied as far as time 

 and circumstances permitted, and are treated of more fully in other 

 publications on this epidemic. 



Varieties attacked. — Most of the cane of the infected district has 

 been of two varieties, the striped or rayada, and the white (hlanca) 

 or Otaheite, probably the same as the old Bourbon cane. The white 

 cane was first attacked and is at present most subject to the disease, 

 the cankers being especially characteristic of this variety. Its elim- 

 ination, as has already occurred in other parts of the Island, seems 

 certain. The rayada during the present year has been in many places 

 as badly attacked as the white, although there is still the possibility 

 that strains from outside districts may remain immune. 



Other varieties grown on a smaller scale and brought in for trial 

 have been quite uniformly attacked, hamhoo, penang, B-3412, B-208, 

 yellow Caledonia, Cavengerie, and others. A dark red variety, locally 

 known as sarangola has been quite resistant but unfortunately is not 

 a good milling cane, nor is it probable that it would have any great 

 degree of resistance if planted on a large scale. 



Comparison iritJi other cane diseases. — This disease can not be con- 

 fused with any of the stalk or leaf diseases described in the earlier 

 part of this paper, the essential symptoms being sufficiently different. 

 Moreover, in no instance has it been possible to find any more evi- 

 dences of any of these than occur in normal fields. Rind disease 

 has been especially watched for since it is the reputed cause of an 



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