626 EXPERIMENT STATION RECORD. 



also of studies regarding the poisonous action of aluminum salts, their effects 

 on the development of fungi, and the question as to whether aluminum is a 

 nutritive element, the results obtained by the author being discussed in con- 

 nection with those bj' some other investigators. 



Salts of aluminum of 0.005 per cent concentration hindered the growth of 

 Zea mays, Vicia faba, Lens esculenta, IlcUanthus nnnnus, etc., while 0.0001 

 per cent somewhat increased growth. Aluminum nitrate showed a toxic effect. 

 Aluminum sulphate in concentrations of 0.005 per cent to 0.1 per cent strongly 

 increased growth and fructification of Aspergillus nigcr in the presence of 

 glycerin, but growth and fructification v\-ere checked when glycerin with pep- 

 tone was added. Aluminum nitrate of 0.01 per cent concentration favored 

 growth of the prothallia of Eqidsetun arvcn.'<e when these were grown on agar 

 w'ith mineral salts. 



The influence of some organic poisons on plant cells, T. Wee^'ebs (Rec. 

 Trar. Bot. A^crlawh, 11 (1914), No. //, pp. SJ2-341, fig. i).— This is a somewhat 

 detailed account of studies on the effects, at different concentrations and at 

 constant or variable temperatures, of some organic substances on beet root 

 parenchyma. 



It is stated that in high dilutions quinin hydrochlorid and chloral hydrate 

 required a very long time to produce fatal effects. Combinations of these and 

 some other organic poisons with organic salts, chiefly of alkali and related 

 metals, were studied, and in tliese cases the toxicity of tho organic poisons was 

 found to be weakened by the presence of the metals. Trivalent ions were more 

 effective than bivalent ions, iniivalent ions being also without (effect. The 

 presence of hydroxyl ions generally opposeil the toxicity of the poisons. The 

 combined influence of poisons and salts was noted in both cell membrane an<l 

 protoplasmic colloids. The possible significance of the observed facts is 

 discussed. 



Smelter fumes injury to vegetation, G. P. Weldon (Mo. Bui. Com. Hort. Cal., 

 /f (J 915), Xo. rt-C. pp. 2.',0-2.'f9, figs. J.}).— The author has collected .samples of 

 more than 40 different species of plants, all of which displayed the character- 

 istic forms of bleaching or burning of the leaves due chiefly to sulphur dioxid 

 gas. It is stated that while it is easy to identify cases of severe in.iin-y where 

 the plant is exposed constantly to the action of the gas, it is difft-rent when 

 the exposure is intermittent, while to determine the extent of the injury is 

 often very difficult or impossible. 



Such factors as moisture, winds, air currents, and drafts from canyons are 

 discussed. It is said to be possible often to detect the odor of sulphur dioxid 

 at 20 miles distant from its source, and it is thought that this slight concentra- 

 tion may cause injury by bringing about a weakening of the plants. Striking 

 differences in resistance are noted even in individual trees of the same species. 



The effects of this gas upon plants, upon productiveness, and upon the ap- 

 pearance and prosperitj' of the country are also dlscusse<l. 



Sexual reproduction, its nature, origin, and consequences, P. A. Dangeard 

 [Botnnifitc. 13. set:. No. .'i-6 {Wt^), pp. 285-325). — This is a discussion of the 

 phenomena and resiilts of sexual reproduction as seen in higher plants, and of 

 analogous behavior in the lower forms. 



The phenomena of sexuality in the Uredinese, Mme. F. Mobeau (Botanistc, 

 13. ser.. No. 4-6 {1914), pp. 145-284. pis. 14, figs. 5).— Following a brief sketch 

 of earlier contril)utions, this article deals mainly with the phenomena of 

 cytogamy, karyogamy, and chromosome reduction, as sh(»wn in a variety of 

 S])ecies of Urcdineu'. and the pr()bal)le significance of such phenomena in rela- 

 tion to the evolution of sexuality. An extensive bibliography is appended. 



