422 EXPERIMENT STATION EECORD. 



stimulatiBg eflfeet of light further showed itself not merely in an increase in size, 

 but also in a change in form. It was further found that, although the arche- 

 gonia and antheridia of ferns are usually produced on the shaded side of the 

 prothallus, where the illumination was equal they were formed on both sides, 

 and there were indications that uniform illumination resulted in an increased 

 proportion of female prothalli. 



The replacement of zinc by uranium, in cultures for Aspergillus niger, 

 C. Lepierre {Gompt. Rend. Acad. Soi. [Paris], 156 {WIS), No. 15, pp. 1179- 

 1181). — According to the author's investigations with uranium nitrate, it is 

 claimed that this salt can replace zinc in Raulin's solution and that it exerts a 

 remarkable influence on the rapidity of the growth of A. niger. 



Some relations between salt plants and salt spots, W. A. Cannon {Leland 

 Stanford Jr. Univ. Pubs., Univ. Ser., Dudley Mem. Vol., 1913, pp. 123-129).— A 

 study was made of plants growing in a salt spot near Tucson, Ariz., where the 

 soil contains a considerable amount of sodium salts. 



Chemical analyses and electrical resistance tests were made of three species 

 of Atriplex, which occur naturally in this area, and it was found that the salts 

 of sodium and calcium were present in unlike amounts in the ash of the plants. 

 The electrical resistance tests showed in general that the resistances were 

 characteristic for the different sjoecies, A. canescens having the highest and A. 

 nuttaUii the lowest resistance. Where the soil solution was most dense and 

 carried the most sodium salts, A. nuttaUii, which contained the largest amount 

 of soluble salts and the largest proportion of sodium, was the most abundant 

 species, while those containing this salt in less amount with an Increased content 

 of calcium were species from the outer portion of the salt spot 



Town smoke and plant growth, C. Crowthee (Jour. Roy. Hort. Soc. [Lon- 

 don], 38 {.1913), No. 3, pp. 461-468). — The author gives a summary of recent 

 investigations on the effect of smoke on plant growth, the principal conclusions 

 being in part based upon experiments noted elsewhere (E. S. R., 26, p. 229). 



The use of the manometer in sap movement, E. Reindees {Rec. Trav. Bot. 

 Nierland, 10 {1913), No. 1, pp. 1-68, pis. 3, ftgs. 7).— The use of the manometer 

 in connection with studies in sap movement is described and an account given 

 of investigations on sap flow in Sorbus americana. 



Structure and life history of bacteria, W. Benecke {Bau und Leben der 

 Bakterien. Leipsic and Berlin, 1912, pp. XII-\-650, figs. 105). — The author has 

 brought together the more general facts and important details concerning the 

 nature, relations, and activity of bacteria, discussing among other topics the 

 culture methods of bacteriology; the morphology of bacterial cells; the system- 

 atic relations of bacteria (based on both morphological and physiological char- 

 acters) and their variability; their general living conditions, stimulation move- 

 ments, and metabolism; dissimilation phenomena, including fermentations; the 

 nitrogen fixing and denitrifying bacteria ; the presence and distribution of bac- 

 teria on the earth ; bacteria of cultivated soil, meadow, forest, and water ; and 

 bacteria as inhabitants of other organisms, both plant and animal, including 

 man. The work concludes with an index of authors referred to and one of 

 subject matters treated. 



Report of the imperial agricultural bacteriologrist, C. M. Hutchinson 

 {Rpt. Agr. Research Inst, and Col. Pusa [India], 1911-12, pp. 78-83).— The 

 author reports investigations on soil bacteriology, stating that the method of 

 determining bacterial activity by plate counts has been abandoned in favor of 

 measurements of the physiological activity of the soil organisms. By use of 

 the latter it is possible to maintain conditions comparable to those in the field 

 and to determine optimum conditions of moisture, eta, for any particular soil 

 as regards ammonification, nitrification, etc. 



