September 15, 1905.] 



SCIENCE. 



337 



stimulation is due to the direction of the rays 

 of light, and not to differences of light in- 

 tensity. In its place he advances the hyiDoth- 

 esis that the direction of the light can act 

 but indirectly by producing differences of in- 

 tensity. In support of this view, it is as- 

 sumed that the perception of light stimuli is 

 localized in the upper epidermis, and that the 

 arched epidermal cells of Ficus, Hedera, 

 Magnolia, Oxalis, etc., and the so-called ocelli 

 of Fittonia, Impatiens and Peperomia serve as 

 definite sense organs for perceiving light. The 

 author proves experimentally by photographic 

 prints of the epidermis that these sense-or- 

 gans concentrate the light upon or near the 

 cytoplasm of the inner epidermal vpall. Fur- 

 ther than this, his exposition, as he himself 

 states, ' oftentimes possesses a purely hypothet- 

 ical character.' The facts gained by the au- 

 thor's experiments are a valuable addition to 

 our knowledge of the intimate details of the 

 reception of light by the leaf. As a whole, 

 however, the book contains far too much specu- 

 lation, and is too miach pervaded by an obvious 

 bias in favor of ' sense-organs.' It is an 

 excellent example of first-class experimental 

 work marred by unscientific treatment of the 

 results obtained. - Pj^ederic E. Clements. 

 The University of Nebraska. 



8oil Bacteria and Nitrogen Assimilation. By 

 Frederick D. Chester. Bulletin 66 (Nov., 

 1904), Delaware College Agricultural Ex- 

 periment Station, Newark, Del. 

 In a bulletin bearing the above title Fred- 

 erick D. Chester records his experiments with 

 free nitrogen-assimilating bacteria. He states 

 that nitrogen-fixing bacteria are present in all 

 soils. Some fi:s nitrogen more actively than 

 others. These microbes are stimulated to 

 greater activity by free soil tillage, due to the 

 fact that they are essentially aerobic and fre- 

 quent stirring up of the soil supplies them 

 with the necessary oxygen (air). Since these 

 low organisms further require organic matter 

 and lime for their food, he advises the liberal 

 supply of these articles to the soil in order 

 that the organisms may multiply rapidly and 

 fix the free nitrogen of the air more actively 

 for the use of higher plants. The more tech- 



nical side of the paper deals with the methods 

 of technique and the culture characteristics 

 of the microbes described. The first part of 

 the paper is historical, reviewing largely the 

 European work along similar lines. It is an 

 exceedingly interesting paper and the reader 

 is advised to consult the original. 



Albert Schneider. 



SCIENTIFIC JOURNALS AND ARTICLES. 



The American Naturalist for August con- 

 tains the following papers: 'A Systematic 

 Study of the Saliacese,' by D. P. Penhallow, 

 containing, among other conclusions, - that the 

 Saliacese as a whole is an old world family 

 with a strong tendency to a boreal habitat, 

 and the present tropical and subtropical mem- 

 bers of the group probably represent the relics 

 of a wider distribution in Cretaceous and 

 Tertiary time. ' Developmental Stages in the 

 Lagenidaj,' by J. A. Cushman. The writer 

 considers that Hyatt's laws of development 

 may be applied to the Foraminifera and that 

 where young individuals can be obtained their 

 relations are usually made out with ease. B. 

 M. Davis gives the seventh of the series of 

 ' Studies on the Plant Cell,' accompanied by 

 a bibliography of papers referred to in sec- 

 tion Y. 



The Popular Science Monthly for Septem- 

 ber has the following articles : 



Charles Iveyser Edmunds : ' China's Renais- 

 sance.' 



Frank Lincoln Stevens : ' The Science of Plant 

 Pathology.' 



J. Madison Taylor : ' Sleep and its Regulation.' 



C. W. FouLK and R. F. Earhart : ' State Uni- 

 versity Salaries.' 



Edwin Ray Lankester : ' Nature and Man.' 



Chas. D. Mabx: 'General Education for Engi- 

 neers.' 



Dudley F. Sicher : ' Quackery.' 



Lawrence J. Burpee : ' How Canada is solving 

 her Transportation Problem.' 



Edward J. Berry: 'The Ancestors of the Big 

 Trees ( Sequoias ) .' 



SOCIETIES AND ACADEMIES. 

 RECENT folk-lore MEETINGS IN CALIFORNIA. 



The first regular meeting of the Berkeley 

 Folk-Lore Club, founded May 3, 1905, was 



