228 EXPERIMENT STATION RECORD. 



rate the samples of soils from different depths, and the results shown by a 

 series of diagrams. 



It was found that nitrifying, denitrifying, and ammonifying bacteria were 

 well distributed and universally present in the soils of the Truckee-Carson 

 irrigation project, and became physiologically active when favorable conditions 

 for their development occurred. The lack of proper decay and humification of 

 organic matter in many of the unproductive soils is due either to unfavorable 

 bacterial conditions produced by certain physiological and chemical factors or 

 to an unusual bacterial flora. The nitrifying bacteria in the soils of Fallon. 

 Nev., are active at greater depths than in eastern soils, and seem to be un- 

 usually virile in solutions, although the data on these points are not conclusive. 



In genei'al, the conditions favor nitrification, which frequently becomes in- 

 tense, while those favoring deuitrification are I'are. 



Upon assimilation of atmospheric nitrogen by fungi, L. H. Pennington 

 {Bill. Torrcii Bot. Cluh, 38 {19] 1), No. 3, pp. /3.5-/.3.9).— The author gives the 

 results of experiments on the fixation of nitrogen by Penicillium, Aspergillus 

 niger, Alternaria, and 3 species of Fusarium, in which no evidence of any fixa- 

 tion of nitrogen by these plants was found. The author believes that some of 

 the positive results obtained by certain investigators on the fixation of nitrogen 

 by fungi are due to errors of observation and technique, or to the use of dif- 

 ferent species of fungi under the same name by different investigators, as it is 

 very possible that some strains of fungi are able to fix nitrogen, while other 

 very similar strains or varieties do not have this ability. 



Experiments with cyanamid-decomposing bacteria, H. Kappen {Centbl. 

 Bakt. [etc.^, 2. AM., 24 (1909), No. 13-15, iw. 382-^04; ahs. in Bot. Centbl, lU 

 {1910), No. 43, pp. 432, 433). — The author claims to have found 4 bacteria, 

 which in lime nitrogen and cyanamid solutions are able to decompose the 

 cyanamid. 



It is further stated that neither carbon dioxid nor organic acids are able to 

 change the cyanamid in culture solutions and in the soil. The favorable action 

 of grape sugar on the decomposition of the cyanamids is not due to the in- 

 fluence of the decomposition products of this kind of sugar, but is attributed 

 to a physiological action on the bacteria. 



It was also found that 2 fungi, Cladosporium and Penicillium hrevicaule, 

 played a part in the decomposition of the cyanamid. 



The clogging of drain tile by roots, G. E. Stone (Torreya, 11 {1911), No. 3, 

 pp. 51-55, fig. 1). — An account is given of the clogging of a 12-inch drain tile 

 by the roots of a pear tree, a single root having penetrated the tile. From its 

 cross section the root was apparently 5 years old. The tile was clogged to a 

 distance of 61 feet. The principal roots removed were measured and the others 

 estimated, from which it appeared that there was a total length of roots 

 amounting to 8,498 feet in the section of tile removed. 



The mycoplasm theory and metachromatic corpuscles, J. Beauverie 

 (Compt. Rend. Acad. Sci. [Paris'i, 152 (1911), No. 10, pp. 612-615).— In a 

 study of cross sections of young rust sorl on wheat leaves, the author found 

 many nucleus-like bodies not only in the fungus hyphae, but also in the neigh- 

 boring cells of the host. These bodies when stained with certain anilin dyes 

 changed from blue to violet, and are called metachi'omatic bodies. The author, 

 therefore, claims that the nuclei of the so-called mycoplasm of Eriksson are 

 nothing more than these metacromatic bodies. 



Variation of fungi due to environment, F. L. Stevens and J. G. Hall 

 (North Carolina Sta. Rpt. 1909, pp. 47-71, figs. 37).— Previously noted from 

 other sources (B. S. R., 21, pp. 33, 626), 



