1917] DISEASES OF PLANTS. 453 



Dendropemon sp., and Phorandendron sp. Some other plant troubles having dif- 

 ferent causes are noted. 



Annual report of the mycologist for the year 1913-14, W. J. Dowson 

 {Dept. Agr. Brit. East Africa Ann. Rpt. 1913-14, PP- 118-121).— A disease of 

 sisal Is thought to be due to climatic conditions. 



The coffee leaf disease due to Hemilcia vastatrix was treated successfully 

 with Bordeaux mixture. Formalin in weak solution was found protective but 

 it retarded germination. 



Diseases identified included the coffee leaf disease (H. vastatrix), rusts of 

 wheat (Pticcinia graminis. P. glumarum, and P. triticina), barley (P. simplex), 

 maize (P. sorghi), peach (P. pruni-spinosce) , fig (Uredo fid), carnation {XJro- 

 mpoed caryophyllinus), bean (U. appendiculatus) , mildew of rose (SpJiwrotheca 

 pannosa), tobacco (Erysiphe communis), cucumber and marrow {E. cichora- 

 cearum), and grape anthracnose (Glososporium ampelophaguni) . Diseases still 

 unidentified include the bud rot of Cocos nucifera, a blackening of the stems of 

 Manihot glaziovii, a root disease of young Juniperus procera, a heart rot of the 

 same plant due to a Fomes, and a leaf disease attacking citrus trees, other than 

 limes. 



Annual report of the mycologist for the year ending March 31, 1915, 

 W. J. DowsoN {Dept. Agr. Brit. East Africa Ann. Rpt. 1914-15, pp. 94-101). — 

 In this report, which is particularly concerned with administrative and other 

 matters, it is stated that coffee is regularly attacked by Uemileia vastatrix, but 

 that the disease is not very virulent and is not considered a dangerous pest 

 if properly handled. The effects on this parasite of seasonal and weather con- 

 ditions, and of various fungicides and combinations thereof, are detailed. 



Withertip of citrus trees is under investigation, the only organism found in 

 connection with the specimens examined being Colletotrichum glceosporioides. 

 Dead leaves on the ground are thought to aid in spreading the disease.. 



Rose leaf mildew (Sphwrotheca pannosa) is reported as again very preva- 

 lent on susceptible varieties. Copper sprays control the disease but scorch 

 the foliage of certain varieties. 



Bud rot disease of the coconut palm, or a root rot disease, or both together, 

 caused mortality among the older trees. Drainage and manuring are con- 

 sidered the only practicable remedies. Of the several bacteria isolated from 

 diseased material, one closely resembled Bacillus coli communis. 



A list Is given of parasitic fungi recorded during 1914-15, in connection with 

 associated plant diseases. 



Some problems connected with the treatment of fungus diseases by spray- 

 ing, E. S. Salmon and J. V. Eybe (Gard. Chron., S. set., 60 {1916), No. 1559, pp. 

 229, 230). — In this paper the authors, discussing some of the results of experi- 

 mentation and practice in the use of fungicides against plant diseases, state 

 that to make this work thoroughly eflScient its problems must receive detailed 

 attention from three sides, relating to the fungus, the host plant, and the 

 chemical substance of the fungicide. These phases are briefly discussed. 



Control of root knot by calcium cyanamid and other means, J. R. Watson 

 (Florida Sta. Bui. 136 {1911), pp. 145-160, fig. 1).—A description is given of 

 plant and greenhouse experiments with calcium cyanamid for the control of 

 root knot on various plants. 



As a result of his Investigations, the author recommends the use of calcium 

 cyanamid thoroughly mixed with the soil, after which the beds are to be well 

 irrigated. This treatment, it is said, will so greatly reduce the number of 

 nematodes as to make the growing of susceptible crops profitable. The amount 

 of cyanamid required will vary from one thousand to several thousand pounds 



