DISEASES or PLANTS. 343 



The author reports the occurrence of Microsphccra euphorbue on roselle, and 

 on the basis of the investisations of Bessey. dusting the plants with sulphur 

 while wet with dew is sujrsested as a moans for control. 



A brief note is given on the occurrence of Fomcs tnarnioraliis on the water 

 oak (QiieiTiis (Kjiutlica). 



Report of assistant plant physiologist, B. F. Floyd {Florida Sta. Rpt. 

 JDOS, pp. XV-.\C]', pi. /). — The investigations reported have been largely c(»n- 

 flned to studies in plant nutrition. Mori)hologica] and cytological studies have 

 been Jiegun on citrus, pineapple, and cassava plants. A description is given of a 

 leaf spot of citrus trees, the exact cause of which is not definitely determined, 

 and of chlorosis of cassava, with which no organisms appear to be associated. 



Winter stage of Sclerotinia fructigena, J. B. Dandeno {Rpt. Mich. Acad. 

 Sci., 10 {1008), pp. 51-53, pis. 3). — A study was made of the winter stage of 

 Monilia fructigcna on plums. In the fall of 1!)05 diseased plums abundantly 

 affected with the conidial stage were planted in various situations to furnish 

 laboratory material. An examination of the material was made and information 

 secured regarding the development of the ascus stage. 



It was found that when infected fruits were placed on the surface of the 

 ground among dead, long grass, near the foot of the trees, there was au 

 abundant production of Sclerotinia, while those in the open, on the naked 

 ground, either on top of the soil or underground, did not produce any. When 

 on top of the soil the fruits completely dried and when underground they 

 rotted without producing the winter forms. 



In sod, where the surface soil is not disturbed and the old fruits are pro- 

 tected by grass, the ascus stage is developed.. This has a practical bearing 

 on the subject of control, and it is suggested that orchards should be plowed 

 in the fall and the ground dug over, thus covering all the old fruits so that the 

 fungus will not survive. The presence of cover crops is held to be favorable 

 for the development of the fungus. 



Citrus diseases, H. S. Fawcett {Florida t^ta. Rpt. 1908, pp. LXIV-LXVII).— 

 The principal investigations carried on by the author during the past year 

 have been on the diseases of citrus trees, particular attention being paid to 

 the scaly bark disease, an account of which has already been given ( E. S. R., 

 20, p. 1045). 



In the present report brief accounts are given of the scaly bark, smoky 

 fungus, withertip. gumming, and scab. 



A disease of the cacao, E. Griffon and C. Maublanc {Bill. Trimest. Soc. 

 Mycol. France, 25 {1909), Xo. 1, pp. 51-58, figs. 2). — A study was made of dis- 

 eased branches and roots of cacao trees, the specimens having been received 

 from French Kongo. These were found to be infested with a fungus which 

 was recognized as that described by rrillieux and Delacroix (E. S. R., G, 

 p. 909) under the name Macrophoma vcstita. 



Further studies were made of the fungus, and as a result the authors 

 claim that a number of the species of fungi described by different authors as 

 attacking cacao are in fact the same species. Of these Botryodiplodia tlico- 

 bromw, Macrophoma vcstita, Diplodia cacaoicola, and Lasiodiplodia nigra 

 should be combined under one species, the proper name of which, according 

 to the rules of nomenclature, would be Lasiodiplodia thcohromw. 



Tea root diseases, T. Petcii {Indian Planters (la;:;., 5t {1909), Xo. 23, pp. 

 795, 791!) . — Attention is called to the apparently selective par.isitism of Roscl- 

 linia hothrina on tea and other plants, spreading from the roots or stiunps of 

 one species to those of another, but often passing related forms. 



In the case of the tea root fungus {Ustulina zonata), which is spread by 

 spores, the fungus is found to grow also on stumps of Grevillea and to cause 



