650 EXPERIMENT STATION RECORD. [Vol.35 



foi* a season under certain conditions. Tests with formalin promise little 

 success. 



Corky scab is said to be very much localized in England and rare in localities 

 where potatoes are grown in large quantities. In a few cases it has been found 

 in a high degree of intensity, proving as destructive as wart disease. No 

 remedy is known for corky scab, to which every variety of potato appears to 

 be susceptible, but it spreads slowly and does not appear to persist in well cul- 

 tivated soil. 



Silver leaf of plums and apples and apple mildew have been studied to some 

 extent. Dilophia graminis has been discovered on wheat in two localities. 



Recent observations on diseases of cultivated plants in Bohemia, A. Kxitin 

 {Yestnik 5. Sjez. Ces. PHr., 1915, p. 427; abs. in Bot. Centbl., 129 {1915). No. 

 15, p. 384). — Observations are recorded on the appearance in Bohemia for 

 the first time of Tilletia Icevis, Peronospora jaapiana, and Typhula graminum, 

 and the reappearance, after some years, of Tilletia secalis. Sclerotinia tri- 

 foliorum has been noted in new localities, and Sphcerotheca mors-uvce appears 

 to have attained wide if not universal distribution. 



Cryptogamic parasites of cultivated plants in and near the Province of 

 Turin in 1913, P. Voglino {Ann. R. Accad. Agr. Torino, 51 {1914), PP- 159-114; 

 abs. in Internat. Inst. Agr. [Rome], Mo. Bui. Agr. Intel, and Plant Diseases, 6 

 {1915), No. 6, pp. 881, 882). — This is an arrangement of the data as collected 

 in 1913 regarding weather and regarding cryptogamic parasites of plants in 

 this region. The diseases noted, while encouraged in some degree by the spring 

 rains, were later held in check by the dryness of the summer season. 



Recent contributions to our knowledge of the genus Gymnosporangium, 

 F. D. Kern {Abs. in Science, n. ser., 43 {1916), No. 1106, p. 364).— The author 

 reviews information regarding the genus Gymnosporangium, supplemental to 

 his previous report (E. S. R., 27, p. 424). Among the more notable points 

 brought out are the reporting of another aecial host outside of the Rosales, the 

 finding of teliospores in the species possessing uredinia, studies of the effects 

 produced by the host on the morphology of the fungi, and active investigations 

 of the species causing diseases of economic importance. 



Cultures of Uredineas in 1915, J. C. Aethue {Mycologia, 8 {1916), No. 3, pp. 

 125-141; abs. in Science, n. ser., 43 {1916), No. 1106, p. 363).— With this report, 

 the fourteenth of a series continued by the author since 1899 (E. S. R., 32, p. 

 750) on the culture of plant rusts, it is proposed to end the series of investiga- 

 tions. 



Besides notes on species giving negative results owing to inadaptation of the 

 racial material used, an account is given of successful cultures supplementing 

 work previouly reported in case of 8 species named and a list of 4 species now 

 reported on for the first time. 



White speck disease of leaves, C. von Tubextf {Naturw. Ztschr. Forst. u. 

 Landiv., 13 {1915), No. 10, pp. 469-415, figs. 3).— The author describes a peculiar 

 leaf decoloration, which is said to be associated with the absence of chlorophyll, 

 starch, and generally plasma in the palisade cells. The affected areas are small 

 but thick. A list is given of woody plants and one of herbaceous plants known 

 to exhibit this phenomenon. 



Further evidence that crown gall of plants is cancer, E. F. Smith {Science, 

 n. ser., 43 {1916), No. 1121. pp. 811-889).— This is a paper read before the 

 Washington Academy of Sciences, in which the author presents further evi- 

 dence that crown gall of plants is cancer, and that cancer in plants, because of 

 its variable form and its bacterial origin, offers strong presumptive evidence both 

 of the parasitic origin and of the essential unity of the various forms of cancer 

 occarring in man and animals. 



