DISEASES OF PLANTS. 149 



Fungi, an attempt at their classification, P. Vuillemin (Lcs Champignons, 

 Essai de Classification. Paris, 1912, pp. VII+.'f25). — This is one of a series of 

 12 vokinies treating of fungi. It contains a historical review of different sys- 

 tems of classification, after which the author treats of the grouping of fungi 

 according to their cytological and biological characters. 



Some new parasitic fungi of Japan, M. Shibai and K. Haea {Bot. Mag. 

 [Tokyo], 25 (,1911), Xo. 200, pp. G9-13, pi. 1; ahs. in Bui. Trimest. Hoc. llycol. 

 France, 21 (1911), No. 3, p. 397). — The authors report, with illustrations and 

 descriptions, the following new species of Japanese fungi : Lophodermium 

 chamwcyparisii, Asterula cham^cyparisii, Phdosphoerella japonica, Lepto- 

 sphcerin cinnamomi. Mycosphwrella paulowni<e, 11. zingiberi, J/, macleyw, and 

 Sp h cer uJ in a auciibo'. 



Notes on the Japanese species of Phragmidium, M. Kasai (Trans. Sapporo 

 Xat. Hivt. *S'of., 3 (1909-10), pp. 21-51, pi. i).— The author describes 17 species 

 of Phragmidium occurring in Japan, 11 of which are peculiar to that country 

 and 3 are new to science. The species occur parasitically on Potentilla, Rubus, 

 liosa, and Sanguisorba. 



Cardinal temperatures for the germination of uredospores of cereal rusts, 

 E. C. Johnson (J.&S. in Phytopathology, 2 {1912), Xo. 1, pp. -'/7, //S).— The author 

 lias made a study of the effect of temperature on the germination of the spores 

 of cereal rusts, believing that it Would throw further light on the relation of 

 meteorological conditions to rust development. The investigations were carried 

 on with the uredospores of Puccinia gra minis on wheat, barley, and oats. P. 

 ruMgo-cera on wheat and rye, and P. coronata on oats. The spores were ob- 

 tained from fresh material, and the germinations were made in distilled water 

 in incubators in which the temperature ranged from 1.5 to 31° C. 



In the experiments the maximum and minimum temperatures for the differeut 

 rusts were as follows: P. graminis, from 2 to 31° ; P. rubigo-vera on wheat and 

 rye, about the same; P. coronnta on oats, a higher minimum, 7 to 8", with a 

 maximum of 30°. 



The optimum temperature could not be definitely determined by percentages, 

 on account of the lack of uniformity between 9 and 25°. From the develop- 

 ment of the germination tube, the optimum temperature appeared to be between 

 12 and 17° for all the forms studied. 



These low cardinal temperatures are believed to explain such points as the 

 difficulty with which infection takes place in excessively warm greenhouses and 

 on hot days; the difficulty of finding viable uredospores in early spring, the 

 majority already having germinated ; and the favoring of rust development and 

 epidemics by subnormal temperatures at the critical infection periods of the 

 host plants. 



A new method of combating smut of cereals, G. D'Ippolito (Boh Qiiind. 

 Soc. Agr. Ital., 16 {1911), Xo. 19, pp. 680-685; ahs. in Riv. Patol. Veg., 5 {1911), 

 Xo. 9, pp. 133). — The main features of this method are (1) steeping the grain 

 in water at from 20 to 22° C. for 4 hours to start the growth of the internal 

 mycelium and (2) placing it in water at 52° for 10 minutes to kill the growing 

 fungus. 



Ergot on oats, C. W. Wabbubton {Boi. Gas., 51 {1911), No. 1\, p. 64, fig. 1; 

 abs. in Centbl. Bakt. [etc.], 2. Abt.. 32 {1912), No. 6-12, pp. 300, 301).— The 

 author reports the discovery at Ames, Iowa, of ergot {Claviceps purpurea) on 

 oats, a disease said to be new in the United States. The attack was noted on 

 a variety immune to smut in July, 1909, a wet season favorable to ergot epi- 

 demics. It did not reappear in the di-y season of 1910. 



Leaf spot of oats, H. Nilsson-Ehle {Sveriges Utsddesfor. Tidskr., 21 

 {1911), Xo. 1, pp. o't-56, pi. 1; abs. in Bot. Centbl, 116 {1911), No. 23, pp. 603, 



