THE DISEASES OF THE SUGAR-CANE. 299 



circulars sent out during 1896, places the annual loss as 

 4'83 per cent, of the crops (equal to about ;^220,ooo ?).^ 

 Besides the sereh, quite a number of parasitic fungi have 

 been described as attacking the leaves and stalks of Java 

 canes, ranging from harmless saprophytes to active and 

 dangerous parasites." 



4. The sugar-growing districts of Queensland and New 

 South Wales, although but recently established, have their 

 full share of animal and vegetable parasites. Most des- 

 tructive of these is the Gumming, thus described by the 

 government pathologist.^ If, as in slight attacks, a " cane " 

 is formed, cavities appear inside the tissues at the top of 

 the stalk, filled with offensive matter, and accompanying 

 the death of the apical tuft of leaves. Where the attack is 

 severe, plants reach the height of one or two feet, and then 

 die back, shooting out again from the base and forming 

 buds half way down the stalk. The vessels, if examined, 

 are found to be full of gum, and this, under high powers is 

 seen to be swarming with bacteria. As a result of careful 

 inoculation experiments, the disease of gumming has been 

 attributed to the bacteria [Bacillus vasculo7'um) which pro- 

 duce the gum and cause the stoppage of the vessels.* 

 While offering many points of similarity with sereh, the 

 Australian disease is readily distinguished by the exudation 

 from cut surfaces, of a clear, yellow mucilage which leaves 

 a bright stain on drying. Gumming is also reported as 

 serious in Mauritius ° and Pernambuco, the sugar-growing 

 province of Brazil.*^ The latest reports show that this 

 bacterial disease has gained a footing in Java, although at 

 present only found in one or two, strictly isolated spots.' 



5. The cane-fields in the West Indies are being devas- 

 tated by a parasitic fungus, recently described as Tricho- 

 sphaeria Saccharic and locally known as the " rind fungus ". 

 In this case the plants frequently grow luxuriantly, and fine, 

 stout canes with good joints are formed. As the time for 

 cutting the canes approaches, to the despair of the planter, 



^Archie/, p. 612, 1896. - Wakker and Went. ^ ^obb (i). 



'^Cobb (2). ^ Boname (i). 



^ Sugar-Cane, !'&()■], wwl,"^. Zn- 'Went (2). ^ Massee (i). 



