452 EXPERIMENT STATION RECORD. 



In studying silver scurf, sonietinios callod " Ibrip marks," the conclusion 

 was reached that a species of fugus, probably a Couiothecium, is one of the 

 main factors in producing the disease. 



! The characteristics of the red rot disease of sugar cane as it exists in 

 Florida and methods for its control are given. The use of only healthy seed 

 canes, dipping the seed canes in a 5 : 5 : 50 Bordeaux mixture just before plant- 

 ing, fall planting of the canes in place of bedding thom, the burning of all trash 

 in the old bed and of all diseased canes, and the gradual introduction of im- 

 mune seedling varieties are suggested as remedies for combating this disease. 



Infectious diseases of plants, F. Tidswell {Rpt. Govt. Bur. Microbiol. N. 

 S. Wales, 1909, pp. 5Jf-72, figs. 21, map 1 ) .—This report includes a list of fungus 

 diseases met with during the year, arranged according to hosts and prepared 

 by H. Johnston, discussions of potato blight and other potato diseases, and 

 experimental researches on bunt of wheat, maize smut, and a disease of banana 

 trees. 



The potato diseases given for New South Wales are as follows: Late blight, 

 leaf spot (Alternaria solani), dry rot (Fusariuni solani), scab (Oospora 

 scaMes), a nematode (Tylenchus devastatrix) , and brown fleck. Brown fleck 

 is a disease which is characterized by the occurrence of rusty brown areas of 

 various sizes and shapes in the flesh of cut tubers. These spots may be one 

 to several in each tuber, either separate or confluent into a large area, involv- 

 ing almost the whole tuber, and consisting of dead tissues. No parasite has 

 yet been found associated with it, and the cause of the disease is unknown. 



The report on maize smut prepared by H. Johnston and that on bunt of wheat 

 prepared by Darnell-Smith have been previously noted from other sources 

 (E. S. R., 22, p. 74.5; 24, p. 347). 



The report on diseases of banana plants prepared by the author and H. John- 

 ston includes a description of a banana disease in which the leaves turn a 

 golden yellow, followed eventually by the breaking off near the ground of all 

 the stalks and suckers, and gives the results of a microbiological examination 

 of the fluid and tissues from the diseased parts. The specimen examined, con- 

 sisting of the stock of a well-grown tree, showed an external irregular patch 

 of several square inches which was discolored and softer to the touch than the 

 surrounding tissue. On pressure a fluid exuded through fissures. Ti-ansverse 

 and longitudinal sections of the stock gave off a foul odor and showed sodden 

 tissues and much free liquid which existed between the leaf sheaths as well as 

 the actual tissue. Sections of individual leaves showed discolored areas of 

 gray, green, and light and dark brown, while the core of the plant was soft 

 and in parts diffluent, its ordinary fibrous character being replaced by a paste- 

 like substance. 



The disease apparently proceeds from below upward. A microscopical exami- 

 nation of the fluid and of diseased tissues revealed the presence of the larvae 

 of 2 flies {Necexareta spinigera and a Phorid), one species of mites (Derma- 

 nyssus), nematodes (Monnochus and Diplogaster), a Fusarium, and 5 species of 

 bacteria, 2 of which were putrefactive bacteria, one a chromogenic bacillus, 

 one a saprophytic bacillus, and one bacillus which in its growth discolored and 

 destroyed banana tissues on which it was grown. 



Protection against plant diseases in Ireland (Dept. Agr. and Tech. Instr. 

 Ireland Jour., 11 {1911), No. 3, pp. //57-//61).— A brief history is given of t"je 

 legislation on the regulation or prohibition of dangerous insect and fungus pests 

 of economic plants, including a summary of the more important acts and orders 

 and the methods of administering them. 



Contribution to the study of the sooty molds, G. Arnaud (Ann. Ecole Nat. 

 Agr. MontpelUer, n. ser„ 10 {1911), Nos. 3, pp. 211-25Ji, figs. 9; 4, pp. 255^30, 



