628 EXPERIMENT STATION RECORD. 



separately capable of fonuiuK Hit' same character. When present in different 

 numbers and in difterent individuals, these units simply form quantitative differ- 

 ences. 



In the light of these added facts as to inheritance, the author believes that 

 the word " mutation " may l)e ai)plied to any inherited variation however 

 small, wliile the word " fluctuation " should be restricted to those variations 

 due to inunediato enviroinnent wliicli do not affect the germ cells and which 

 are not inherited. Tliis jiives a rational basis for the origin of new characters 

 which lias heretofore been somewhat of a Mendelian stumbling block. 



Color inheritance in Lychnis dioica, G. H. Shull (Amcr. Nat., 44 (li)lO), 

 No. 518, pp. S3~9J). — In the purple-flowered form of Lychnis it was observed 

 that some of the flowers were of a blue-purple hue, and an effort is made by 

 the author to determine the relationship of this color to the more common 

 reddisli-])urple by crosses between the red and blue, using a single red-flowered 

 individual as the mother in one series of crosses, and a single blue-flowered 

 individual as the mother in another series. The same blue-flowered and red- 

 flowered i)]auts were also crossed at the same time with white-flowered plants. 

 The actual and theoretical results of these eight crosses are given. 



As a result of these experiments the purple color in L. dioica was found to 

 be a compound color due to three distinct and independent genes in a manner 

 exactly analogous to the similar colors in Lathyrus, Matthiola, etc. 



Genetical studies on OEnothera, I, B. M. Davis (Anier. Nat., 44 (1910). No. 

 518, pp. 1 08-11 .J). — The author makes a report on the behavior in the first 

 generation of sets of hybrids obtained by crossing certain species of O<]nothera. 

 The characters of the parents as presented in each cross were so blended that 

 as regards the measurements of parts, habit, texture of foliage, etc., the average 

 for each set of hybrids would probably present a fair mean between the two 

 parents. There was, however, a wide variation in the resemblance of the 

 hybrids to one or the other of the parents. No dominant parental character 

 was discovered in these hybrids. 



Future methods of soil bacteriological investigations, H. J. Conn (Centbl. 

 Bakt. [etc.], 2. Aht., 2.7 {1!)09). No. 1J,-1S. pp. .'/.5.}--'/.57). — The author claims 

 that before any real advances can be made in soil bacteriology the bacterial 

 flora of the soil must be properly classified by means of pure cultures and 

 arranged in well-defined groups. A study must then be made of the effects of 

 the recognized and significant species on the soil rather than on liquid culture 

 media. 



Studies on the micro-organism producing the legume tubercles, G. de 

 Rossi (Ann. Bot. [Rome], 7 (1909), No. .'/, pp. 617-669, pi. 1, fig. 1).—The 

 micro-organism producing the tubercles on the roots of leguminous plants is 

 claimed to have been isolated, its microscopic, biological, and macroscopic 

 characteristics described, and methods for using the organism in practical 

 agriculture given. The organism was isolated by using for inoculation mate- 

 rial water infusions of the contents of the bacteroids, plated on gelatin made 

 from legume glucose, and then replated from the resulting individual colonies 

 until a pure culture was obtained. The bacteina thus isolated were capable 

 of producing nodules on the i-oots of various legumes, and the author claims 

 that the micro-organism is not identical with Bacillus radicicola as described 

 by Beijerinck. 



Research, on the proteolytic enzyins in fungi and bacteria, R. M. Wilson 

 (Notes Roy. Bot. Gard. Edinb., 1909, No. 21, pp. 27-37 ) .—Several species of 

 fungi and bacteria were examined for proteolytic activity. Each species of the 

 higher fungi was ground up in a mortar with water and sand into a thick paste 

 which was diluted with water and then filtered. To the filtrate was added 



