AGRICULTUKAL BOTA.NY. 223 



Measuring the transpiration of emersed water plants, C. H. Otis {Rpt. 

 Mich Acad. ScL, 13 (1911), pp. 250-253, pis. 2).— A description is given of a 

 form of tanlc devised by the author for measuring the evaporation of emersed 

 water plants. 



It was found that unsubmerged water plants transpire large quantities of 

 water, and that this tal^es place principally during the day time. In the case 

 of the one exception, the water lily, the presence of the plants in the tanks 

 materially retarded evaporation from the free water surface. 



The relative wilting coefficients for different plants, Ij. J. Briggs and II. L. 

 SiiANTz (Hot. Gaz., 53 (1012), No. 3, pp. 229-235) .—Observations have been 

 made of a considerable nimiber of plants growing in different types of soil to 

 detei-mine their wilting coefficient (E. S. R., 26, p. 822). These included cereals, 

 grasses, and wild plants from semlarid and arid regions, and the results 

 obtained led the authors to conclude that the variation exhibited in the wilting 

 coefficient of different plants is much less than has hitherto been supposed, and 

 that it is insignificant compared with the range in moisture retentiveness 

 exhibited by different soils. 



Only slight differences were found to exist among the various crops in their 

 ability to reduce soil moisture content before uniting occurs. Sorghum, millet, 

 wheat, oats, barley, and the grasses are practically the same. Rye and rice 

 appear a little lower than the mean, and corn and the legumes slightly higher. 



Conditions which affect the branching of roots, Lulu M. Newlon (Rpt. 

 Mtcli. Acad. Hci., 13 (1911), p. 200). — Observations were made on a number of 

 species of plants to determine the factors which iafluence the branching of 

 roots. It is a well-known fact that when roots aro Injured at their tips they 

 produce lateral rootlets, but the experiments, in which about 1 dozen species of 

 plants were used, indicate that contact does not act as a stimulus for the pro- 

 duction of lateral roots. In most of the plants lateral roots were freely pro- 

 duced in the soil. In some aquatic and semiaquatic plants light inhibited the 

 growth of the roots, while in the terrestrial plants, when the roots were under 

 water, the lateral branching took place with equal freedom in light and In 

 darkness. 



Agricultural microbiology, E. Kayseb (MicroMologie Agricole. Paris, 1910, 2. 

 ed., rev. and cnh, pp. .'/SI, figs. 95). — This is a revised and enlarged edition of 

 a work previously noted (E. S. R., 17, p. 849). 



Soil fungi, H. X. Goddard (Rpt. Mich. Acad. Set., 13 (1911), pp. 208-21Jf).— 

 A preliminary report is given of fungi found in soils, which indicates an abun- 

 dant fungus flora which is conspicuous, rather uniformly distributed, and con- 

 stant in different soils. Tillage and manuring, so far as observations have 

 gone, seem to produce little change in the species and number of individuals 

 present. Many of the fungi show variability in their structural characters 

 when cultivated on media of constant composition. One form, which showed 

 the structural characters of Fusarium and Cephalosporium, is thought to be 

 the probable cause of a wilt disease which attacks several species of garden 

 plants, including asters, sweet peas, zinnias, and Salvia splendens. 



The occurrence of Zygorhynchus moelleri in Michigan, H. Grossman (Rpt. 

 Mich. Acad. Sci., 13 (1911), pp. 20^-207, figs. S).— The author reports the dis- 

 covery in soil samples of Z. moeUeri, a rather common soil fungus of Europe. 



Foi'mation of volatile acids after fermentation, A. Osterwalder (Cenfbl. 

 Bakt. [etc.], 2. AM., 32 (1912), No. 20-25, pp. 481-498).— The author studied 

 the after growth of several yeasts in fruit and grape juices with reference to 

 the simultaneous production of volatile acids, with findings substantially as 

 follows : 



53861°— No. 3—12 3 



