152 EXPERIMENT STATION RECORD. [Vol. 41 



Latex and rubber from upper and lower cut, O. de Vries {Arch. Rubbercult. 

 Nederland. Indie, 3 (1919), No. 3, pp. 12j^-129). — Analyses made by the author 

 indicates that where two cuts are made on one quarter of a rubber tree the 

 Uitex from the upper and lower cut may for practical purposes be regarded as 

 identical in quality. 



DISEASES OF PLANTS. 



Physiological specialization of parasitic fungi, G. M. Reed {Brooklyn Bot. 

 Gard. Mem., 1 {1918), pp. 348-409). — This paper is the outcome of an attempt 

 to bring together the results of numerous investigations bearing on specializa- 

 tion of fungi in connection with particular hosts. It deals extensively with the 

 Uredinese, the Erysiphacese, and other fungi in relation to other plants as 

 normal or as bridging liosts. It is considered especially desirable to know the 

 exact host relations of the different races, as well as to determine whether the 

 races are stable and constant or whether they are capable of a change in viru- 

 lence and consequently able to extend their host range. 



Studies in the genus Gynmosporangium.—I, Notes on the distribution of 

 the mycelium, buffer cells, and the germination of ^cidiospore, B. O. Dodge 

 (Brooklyn Bot. Gard. Mem., 1 (1918), pp. 128-140, pi. 1, pjs. 5).— The author re- 

 ports briefly studies designed to determine the distribution of the mycelium 

 of Gymnosporangium in the different portions of an infected plant. 



A method of obtaining abundant sporulation in cultures of Macrosporium 

 solani, L. O. Kunkel (Brooklyn Bot. Gard. Mem., 1 (1918), pp. 306-312, figs. 

 4). — Having employed in work previously noted (E. S. R., 31, p. 730) a method 

 of retarding growth of Monilia sitophila by lowering the vapor tension of the 

 atmosphere above the pure cultures, as a result of which the fungus was made 

 to fruit more abundantly than in a moist atmosphere, the author employed 

 this treatment in an effort to induce sporulation in MacTosporium solani. It 

 was found that this fung-us would fruit profusely when growing in any of the 

 media employed under such conditions, especially if the mycelium was 

 wounded after the culture had obtained a good start as here described. Con- 

 trasts were noted as observed between M. solani, M. tomato, and M. daturce 

 when these fungi are grown side by side in pure cultures. 



Notes on some methods and terms employed in studying the TJredinales, 

 H. R. Rosen (Phytopathology, 8 (1918), No. 11, pp. 581-583).— The author de- 

 scribes the methods and terminology used by J. C. Arthur and those associated 

 with him in preparing the data relating to rusts published in the North Ameri- 

 can Flora. 



The TJredinales of Oregon, H. S.. Jackson (Brooklyn Bot. Gard. Mem., 1 

 (1918), pp. 198-291). — This represents work by the author and others in col- 

 lecting material in several portions of Oregon. In all 220 species are recorded 

 as occurring on 500 host plants, the number of species being considered as 

 worthy of mention on account of their economic bearing. All the grain rusts 

 yet recorded for North America are known to occur in the State except the corn 

 rust (Puccinia sorghi). All the rusts which are troublesome to florists are 

 represented. The Pacific coast rust of pears and quinces threatens to become 

 of economic importance. Many partially known rusts are found in this section. 

 Notes on distribution are given in some cases. The genera are listed alpha- 

 betically and the species thereunder with their host plants. 



The relations of crown gall to other overgrowths in plants, E. F. Smith 

 (Brooklyn Bot. Gard. Mem., 1 (1918), pp. 448-453). — The author proceeds upon 

 the expressed belief that all overgrowths are correlated phenomena, the 

 response of the organism to essentially similar, but not necessarily identical 



