1917] DISEASES OF PLANTS. 149 



colonial German territory, also in some neighboring countries or foreign lands. 

 Tlie results are briefly indicated of tests with several proprietary or standard 

 fungicidal preparations. 



The genus Meliola in Porto Rico, F. L. Stevens {III. Biol. Monographs, 

 2 (1916), No. Jf, pp. 4TS~554, P'>^- 5). — The author has described material col- 

 lected in Porto Rico during 1912, 1913, and 1915. This has been arranged in 

 95 species and 6 varieties of Meliola parasitic on 171 different hosts, 146 of 

 which are said to be new to Porto Rico for Meliola. 



Specialization of parasitic fung'i, particularly of the cereal rusts, L. Monte- 

 HABTiNi {Riv. Patol. Veg., 8 (1916), Nos. 2, pp. 33-U; 6-7, pp. 145-158).— The 

 author, besides giving a bibliographic discussion of this subject, describes a 

 number of his own investigations. 



He concludes that parasitic fungi are extremely sensitive to the chemical 

 composition of the nutritive medium on which they live, and under its influence 

 easily acquire characters of adaptation which attain to a certain fixity. In 

 consequence fungi may become unable to flourish on species different from that 

 to which they have accustomed themselves, and even on other portions of the 

 same plant which they inhabit, o* in different developmental stages or other 

 conditions of such plant or organ. This unfitness may manifest itself in differ- 

 ences of germinability or of virulence of the spores originating in different 

 situations. 



In grain rusts, or at least in Puccinia ruhigo-vera of rye, which has been made 

 the object of special study by the author, it is stated that these may pass from 

 one to another species of fall or spring wheat and oats, infection varying in an 

 irregular manner even within a single species and a given stage. This matter is 

 further complicated by atmospheric conditions and the influence thereof upon 

 sensitivity to attack as well as upon the infecting bodies. It is thought that 

 temporary adaptation and differences or parallelism of development in both 

 host and parasite may explain what are considered real specializations. 



Some septorias of wheat, W. B. Geove (Gard. CUron., 3. ser., 60 (1916), Nos. 

 1556, p. 194, fiffs- 3; 1551, p. 210, fig. 1). — The author gives the results of com- 

 paring a number of Septorias on wheat sent from west Australia by F. Stoward 

 with some collected in England by J. W. Ellis or by himself. 



Practical or complete identity appeared in several cases, some apparent dif- 

 ferences arising from such causes as different positions of the fungus on the 

 host plant or age of the different portions attacked. /S. nodorum is thus appar- 

 ently identical with S. gluviarum. A specimen causing a dry blight in west 

 Australia is apparently identical with S. graminum iu England, though in some 

 respects another specimen approached S.. ophioides and may prove to be identi- 

 cal therewith. Other forms or modifications are described, in particular S. 

 graminum crassipes. S. hromi and S. bromi brachypodii are thought to belong 

 to the same species, which is probably widespread, and S. tritlci is probably a 

 closely allied form. 



Smut of wheat, F. E. Devoto (Min. Agr. Nac. [Buenos Aires], Dir. Gen. 

 Ensenanza e Invest. Agr. [Pub.] No. 53 (1916), pp. 7-12, figs. 5). — ^This is a 

 discussion of the development, effects, and treatments of the wheat smuts 

 Tilletia tritici and T. Icevis, with directions for the preparation of Bordeaux 

 mixture, which appears to be in common use in this region. 



Some bacterial diseases of vegetables found in Ontario, D. H. Jones (On- 

 tario Dept. Agr. Bui. 240 (1916), pp. 24, figs. Si).— This bulletin deals with 

 bacterial diseases according to the four general types of change they induce in 

 the host, namely, soft rots, wilts, cankers or blights, and galls. 



The cause of bacterial soft rot of various fleshy vegetables, considered as 

 practically one and the same organism, has been discussed under the various 



