margin, and yellowish brown in color. It has been observed on T. 77, 

 Otaheite, Rayada, Sarangola, and in fact all varieties growing in 

 the western end of the Island. 



Relminthosporium sacchari has been reported (generally as Cer- 

 cospora sacchari) from Hawaii (54), the Philippines by Barrett in 

 1911, Java (53, 93), Reunion, and British India (12). It was orig- 

 inally described by Van Breda de Haan and redrescribed by Butler 

 who placed it in its present genus. By none of these workers has 

 any serious damage been attributed to it. 



Helmint^hosporium sacchari Butler. 



Cercospora sacchari Van Breda de Haan. 



Hyphae dark, cobwebby, arising from the center of an elongate 

 brown spot on the leaf-blade ; sporophores more or less erect with 

 single terminal spores; spores several septate with very thick walls, 

 rounded at both ends, 32-90 X 9-14 microns, on conidiophores 120-160 

 mu. long. 



Porto Rico. — On cane leaves, Rio Piedras, January 22, 1914, 1642. 

 April, 1917, 6418, June, 1917, R. C. Eose, 6550 ; Camuy, Jan. 4, 1917, 

 6078 ; Quebradillas, December 1916, 5900. Original determination 

 by J. A. S. (PI. XXIX, fig. 4, 5.) 



RING SPOT OF THE LEAF {Leptosphacria sacchari.) 



This is one of the most common cane fungi of Porto Rico. It is 

 found in practically all cane fields, being usually most abundant on 

 the windward side. Practically every variety will show some infec- 

 tion, although there is great variation in susceptibility, yellow Cale- 

 donia and the white bamboo for instance being quite free as a rule. 

 The amount of disease present also varies in different sections of the 

 Island. Some loss is occasioned by destruction of leaf surface, and 

 in connection with poor growing conditions, or other weakening in- 

 fluences, there may be a heavy loss. 



The spots produced by this fungus are usually very numerous, 

 oval in outline, 5-10 millimeters in breadth by 7-15 in length, dull 

 graj' at the center with a definite red or red-brown margin several 

 millimeters in width. There is often an indistinct yellow halo sur- 

 rounding each spot. The spots not only have a tendency to coalesce 

 but the tissue between turns yellow and the entire leaf as a result 

 withers. This action, however, takes plaee slowly. Conidia are pro- 

 duced on the lower surface of the spots, obtuse angled, black. 3-5 

 septate, the central or two central cells being larger than the apical 



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