330 EXPERIMENT STATION RECORD. 



Recent investigations on the role of hydrocyanic acid in plants, III, M. 

 Treub (Ann. Jard. Bot. Buitenzorg, 2. ser., « (1909), pt. 1, pp. 85-118, pis. 6; ubs. 

 in Naturw. Rundschau, 25 (1910), No. 12, pp. L'fl, 1^8).— The author concludes 

 and summarizes his investigations begun in 1S95 on the presence of hydrocyanic 

 acid in plants (E, S. R., 19, p. 932). In the present paper the results of his 

 studies on sorghum, passion flower, Alocasia macrorhisa, Hevea hrasiliensis, 

 and Prumis javanica are discussed at length. 



In reviewing the previous work the author claims that nothing has been 

 brought to light to invalidate his conclusion that hydrocyanic acid plays an 

 important role in plant nutrition and that It' is a plastic material in the forma- 

 tion of albuminoids. The presence of carbohydrates is fundamental to its 

 foi'mation, and inorganic substances furnished by the soil through the sap of the 

 plant are a second requisite for its formation. He claims that recent investi- 

 gations have confirmed his earlier hypothesis, which, briefly stated, is that 

 hydrocyanic acid is the first recognizable product in the assimilation of nitro- 

 gen in plants and that it is probably the first organic nitrogenous compound 

 formed by them. 



Chlorophyll assimilation of carbon, G. Kimpflin (Essai sur VAssimilation 

 PhotoclilorophyUicnnc du Carbone. Thesis, Univ. Lyon, 1908, p. 159, figs. 13; 

 rev. in Bot. Ccntbl., 113 (1910), No. 10, pp. 2/,8, 2//9).— After a historical 

 resume of the subject, the author gives a discussion of some of the modern 

 theories regarding photosynthesis. Following this are accounts of experiments 

 with green and etiolated plants, the effect of illumination, etc. 



In studying the biological phenomena of photosynthesis, the author found 

 that after illumination a certain period of time must follow before the carbon 

 dioxid assimilation can begin, and conversely that it is continued beyond the 

 time of illumination. His experiments show that the plant makes use of 

 formaldehyde in the synthesis of its carbohydrates and that by the use of cer- 

 tain reagents it is possible to recognize formaldehyde in the parenchyma of 

 the leaf. It appears to be localized and in connection with the chloroplasts, 

 and consequently does not manifest an injurious action on the protoplasm. 

 The author considers chloroi)hyll in plants as the agent for the transposition of 

 light and electrical energy. 



A bibliography of nearly 500 titles concludes the paper. 



[Nitrogen content of nodules and rootlets of immortelle trees], P. Car- 

 MODY (Ann. Rpt. Dcpt. Agr. Trinidad and Tobago, 1908-9, p. J/l). — The nodules 

 were found to contain considerably larger percentages of nitrogen than the 

 rootlets. The difference, however, was smaller when the trees were in flower. 



The toxic properties of tannin, M. T. Cook (Abs. in Science, n. ser., 31 

 (1910), No. 802, pp. 151, 752). — The author has carried on experiments to 

 determine the toxic properties of tannin when added to media in which different 

 species of fungi were grown. 



None of the species of Glceosporium or Colletotrichum was found to give 

 maximum growths in media containing more than 0.4 per cent, while the 

 majority gave the best growth where no tannin was present. Species of 

 Fusarium, Neocosmospora, Cladosporiuni, SphsTpropsis, Sclerotinia, and Phoma 

 were more resistant than Glceosporium, but none gave maximum growths in 

 media containing more than 0.6 per cent. Si)ecies of Penicillium were found 

 to be retarded for a time, but they had a tendency to overcome the toxic action 

 of the tannin. 



The experiments have been duplicated and comparisons made of the gi-owth 

 of organisms in media in which the proteid and tannin formed a precipitate 

 and in media in which proteid was not used. Experiments were also made to 



