548 EXPERIMENT STATION RECORD. 



Ttie leaves seem to be first attacked, and the disease spreads from the lower to 

 the upper part of the plant, discoloring the leaves, which finally become brown 

 and dried. A technical description of the organism is given. 



Notes on winterkilling' of forest trees, C. P. Hartley (Forest Club Ann. 

 [Univ. Nebr.], 4 (1912), pp. 39-50). — The author gives an account of observa- 

 tions made in District 2 of the United States Forest Service of injuries to trees, 

 the different types of which are grouped under the general term of winterkill- 

 ing. Particular attention is paid to the injury which occurred in the Black 

 Hills Forest in 1909 during one of the Chinook periods, or at the time when 

 an unusual rise in temperature was followed by a very sudden and decided fall. 



A new leaf disease of the white alder, F. W. Negee (Aatiirw. Ztschr. Forst 

 u. Landw., 10 (1912), No. 6, pp. SJ/o-SoO, figs. 2). — ^An account is given of a leaf 

 spot disease of Alnns incana in Norway. The fungus causing it does not seem 

 to be identical with any known species, and it is provisionally described as 

 GnomonieJIa albomaculans n. sp. 



The chestnut bark disease, W. H. Rankin (Abs. in Phytopathology, 2 

 (1912), No. 2, p. 99). — A study of specimens of the mature perithecial stage of 

 the fungus showed the perithecia dehiscing under moist conditions throughout 

 the summer. The conidial stage of the fungus, differing from the usual 

 pycnidia, was found commonly developing on the wood. The sap wood was 

 said to be markedly affected and the leaves killed through a toxic effect. The 

 author claims there is evidence that the relative water and air content of the 

 tree determines its susceptibility to the fungus. 



The oak mildew, E. Griffon and A. Maublanc (Bui. Trimest. 8oc. My col. 

 France, 28 (1912), No. 1, pp. 88-lOJf, pis. 3). — The results are given of a series 

 of investigations on the different powdery mildews occurring on the oak, the 

 authors concluding that the American species of Microsphtera on the oak are 

 M. abbreviata and M. extensa, and that they are both distinct from M. alni of 

 Europe. The species occurring on the oak in Europe is said not to be identical 

 with any of the American species, but is probably an introduced one of un- 

 known origin, and the authors propose for it the name M. alphitoides. 



The Hendersonia disease of Eucalyptus globulus, A. R. J3avis (Pomona 

 Col. Jour. Econ. Bot., 2 (1912), No. 1, pp. 2^9-251, figs. 2).— The author describes 

 H. eucalypticola, an apparently undescribed species occurring on the leaves of 

 eucalyptus in southern California. The fungus was apparently distributed over 

 quite an area, but the actual damage being done by it at present seems to be 

 slight. Its attacks seemed to be confined exclusively to the -young broad leaves, 

 the slender longer leaves being, so far as the author has observed, immune to 

 attack. 



Two fungus diseases of coniferous trees, J. Fisher (Agr. Jotir. Union So. 

 Africa, 3 (1912), No. 3, pp. 389-391, figs. 2).— Two leaf cast diseases are re- 

 ported at the Central Exi^eriment Farm, Natal as killing terminal and lateral 

 shoots and in some instances trees. One of these diseases said to be due to 

 Diplodia pvtiea, is supposed to be confined to the genus Pinus. The other, as- 

 cribed to Pcstalozsia funerea, is reported on Pimts pinaster, P. canariensis, P. 

 longifolia, P. insignis, P. massonianu, Cupressus lusitanica, C. lawsoniana, 

 Casuarina leptoclada and possibly on CaUitris australis. Wounds made by hail 

 or in handling and wet weather favor the development of the disease. Protective 

 measures suggested include removal and burning of infected or suspected parts, 

 avoidance of diseased ground in planting susceptible trees, and care in selecting 

 nursery stock and handling young trees. 



The superficial tension and wetting power of insecticides and fungicides, 

 and means for increasing their wetting power, Y. Vermorel and E. Dantony 

 (Compt. Rend. Acad. Sci. [Paris]. 15^ (1912), No. 20, pp. 1300-1302; reprint, 



