512 JOUENAL OF THE EOYAL HORTICULTURAL SOCIETY. 



gives a very full description of a small part (the Gross Kessel) of these 

 mountains. He distinguishes the following associations: — - 



(1) The upper Sudetic fir wood of the lower slopes and spurs; 

 (2) the formation of Kriippelholzer " (bush or scrub), with Picea, 

 Pyrus Aucuparia, &c., to about 1300 metres; (3) the mountain heath; 

 (4) " Quellfiuren " (water-sides and wet ground); (4) the moor; (5) rock 

 and gravel formation. 



Lists are given of the characteristic plants, as well as of the mosses 

 and lichens in each of these formations. The flowering plants are 

 classified as follows : cosmopolitan, circumpolar, circumpolar alpines 

 (high mountain plants), European, Euro-Siberian, Eurasiatic, and 

 European alpine plants. 



In most cases also an attempt is made to describe the various 

 " facies " which occur in the larger groups. 



There are in the mountain heath formation, for example, some 

 " facies " in which Cryptogams preponderate, as, e.g., Mossed Lichen, 

 which occurs on dry soil deficient in plant food, and Athyrium alpestre, 

 which occurs on sufficiently wet ground with humus. Also in the same 

 formation are such facies as the Nardus, the Juncus trifidus, the 

 Calluna, and the Vaccinium Myrtillus facies. 



It will be seen, therefore, and especially as the descriptions of these 

 facies are not only very clear but very complete, that this paper should 

 certainly be consulted by British botanists who are interested in ecology 

 or vegetation surveys. — G, F. S.-E, 



Plant Diseases in Nebraska. By E. Mead Wilcox and E. E. 

 stone {U.S.A. Exp. Stn. Nebraska, 22nd Ann. Rept. pp. 25-63: 

 1909). — This paper might be described as a short, practical handbook 

 of 74 of the most important fungus pests in Nebraska. The symptoms 

 and general life-history of each of these disease fungi are given in a form 

 which should be quite easily understood by the average layman. 

 Keferences to recent papers on these fungi are also given, and there is a 

 short account of the preparation and uses of ammoniacal copper car- 

 bonate, lime-sulphur, and other fungicides. — G. F. S.-E. 



Plant Diseases in S. California, 1906-1909 (U.S.A. Exp. 



Stn. California, Bull. 203; 1909). — The report gives a general 

 description of the work of the various experimental stations in Cali- 

 fornia. 



Pear blight has been found to be due to a bacillus. The leaves, 

 flowers, shoots, and body of the tree near the ground are affected. 

 A large amount of infection is carried by insects, and many trees 

 become infected near the ground or in the butt below the surface of 

 the soil. From there the blight spreads to the roots and kills the tree. 



Eemedies suggested are : (1) careful cultivation ; (2) keeping the 

 trunks clear of shoots and suckers, as infection takes place through 

 the latter; (3) use of immune or disease-resistent stocks. 



The stock known as ' Le Conte ' has proved best for Bartlett pears, 



