1918] DISEASES OP PLANTS. 651 



Counties Soc, 5. ser., 11 {1916-17), pp. 158-162).— This trouble is said to have 

 caused extensive loss to tlie growers of blaclv currants in recent years. It is 

 briefly described according to the characteristics usually displayed. The 

 presence of the bud mite is not considered fully adequate to explain the effects 

 observed. 



Grape downy mildew, M. Gieaed (Vie Agr. et Rurale, 7 (1917), No. 18, pp. 

 S17S19, fig. 1). — This is a general account of data collected by several persons 

 from the study of grape downy mildew (Plasmopara mticola) and of measures 

 for its control. 



Sulphur mixtures for treating Oidium, L. Ravaz (Prog. Agr. et Vit., S4 

 (1917), No. 4, pp. 77-84). — The author, reporting results of tests of grape 

 varieties, as suggested by the differences in the results obtained by some ex- 

 perimenters, states tliat the materials usually added (ashes, lime, etc.) have 

 no other value than to dilute the sulphur. This latter may be used in pure 

 form or with admixtures, according to such circumstances as violence of attack, 

 susceptibility of the variety in question, and cost of materials. 



Studies on the diseases of the raulberry, G. Aenatjd (Min. Agr. [France], 

 Ann. Serv. ^piphyties, 3 (1914), pp. 25-30). — Continuing to report on mulberry 

 diseases (E. S. R., 33, p. 54; 36, p. 751), the author gives an account of the 

 study of mulberry gummosis (Bacterium mori) in 1914, as regards the develop- 

 ment of the infection, alterations in the leaves, and the incubation period in the 

 branches. 



Careful observation has failed to confirm the supposition that aphids (Aphit 

 evonymi) are instrumental in the transmission of infection. Hail injury does 

 not appear to be sufficient explanation for all cases. Uninjured leaves do not 

 seem to become infected. The incubation period appears to be long and to 

 depend largely upon weather conditions. 



Visit to Upper Rewa to investigate leaf diseases of the banana, C. H. 

 Knowles (Dept. Agr. Fiji Pamphlet 24 (1916), pp. 5). — Bananas in the areas 

 visited appear to be affected by leaf-spotting fungi, of which Cercospora muscB 

 and another fungiis, probably a Dothidella, are mentioned. 



Walnut diseases, P. Paementier (Vie Agr. et Rurale, 7 (1917), No. 22, pp. 

 S98-396, figs. 6). — The author lists with brief discussion parasitic animals and 

 plants and nonparasitic injurious influences affecting the walnut. 



Dying of young pines in circles about ant hills, F. W. Haasis (Jour. For- 

 estry, 15 (1917), No. 6, pp. 763-771, figs. 5). — Having made a collection of data 

 since 1915 on the dying of young pines around ant hills in the 1908 plantations 

 at Portland, Conn., the author states that the phenomenon is associated usually, 

 but not always, with ant hills, both Foimica exsectoides and F. fitsca sub- 

 sericea being noted in this connection. The trouble, which occurs in both planta- 

 tions and wild stands, is usually associated with fungus and scolytid infesta- 

 tions, 9 species of fungi having been isolated from the diseased areas. The trou- 

 ble probably originates at a lenticel. Negative results were sometimes obtained 

 from bark inoculations. The ants are thought to be instrumental in the spread 

 of the disease. The infection appears to be primary. 



Summary of blister rust situation in Massachusetts, H. T. Fernald (Mass. 

 Forestry Assoc. Bui. 119 (1916), pp. 23-25, fig. 1).—In the spring of 1915, the 

 white pine blister rust was known in only a few localities in Essex County 

 and the central and western portion of the State. In the fall of that year, the 

 organism was found on currants and pines in Berkshire County. Federal and 

 State scout work showed that Ribes was diseased in 205 towns of the State 

 and pine of all ages in about 45 towns. Removal of Ribes on a large scale is 

 noted. 



