426 PHYSIOLOGY [Bot. Absts. 



50° had no effect on germination. Seeds taken from the ground showed less vitality than 

 those picked from the tree, but removal of the pulp increased and hastened germination.— 

 Otis F. Curtis. 



2901. Stapledon, R. G., and Margaret Adams. The effect of drying on the germination 

 of cereals. Jour. Bd. Agric. Great Britain 26:364-381. 1919.— See Bot. Absts. 3, Entry 

 1889. 



REGENERATION 



2902. Nagai, Isaburo. Induced adventitious growth in the gemmae of Marchantia. 

 Bot. Mag. Tokyo 33 : 99-109. 5 figs. 1919.— Gemmae treated with 10 per cent KNO s (and 

 similar hypertonic solutions) exhibited many cells plasmolyzed but not killed. When these 

 plasmolyzed gemmae were cultivated in Knop's solution some cells died and the growing points 

 were usually decidedly retarded. When apical growth was strongly inhibited numerous 

 superficial cells became active and produced adventitious growths, varying from filaments to 

 heart-shaped thalli. A decided positive correlation was found to exist between apical retar- 

 dation and adventitious growth. Starch is formed abundantly in the old cells of the gemmae 

 but not in those arising from the apical meristem subsequent to treatment. Drying and 

 mechanical injury were found not to be effective stimuli in the production of adventitious 

 growth. The author concludes from this that plasmolysis alters the structure of the proto- 

 plasm in such a way as to cause a 90° rotation of the axis of growth. — Leonas L. Bxirlingame . 



TEMPERATURE RELATIONS 



2903. Chandler, W. H. Winter injury in New York State during 1917-1918. Proc. Amer. 

 Soc. Hortic. Sci. 15: 18-24 (1918). 1919— See Bot. Absts. 2, Entry 723. 



2904. Fryer, J. R. Germination of oats exposed to varying degrees of frost at different 

 stages of maturing. Agric. Gaz. Canada 6: 337-339. 1919.— See Bot. Absts. 3, Entry 1362. 



2905. Lauritzen, J. I. The relation of temperature and humidity to infection by certain 

 fungi. Phytopath. 9: 7-35. 1919— See Bot. Absts. 3, Entry 2679. 



2906. Malte, M. O. Sugar content and its relation to winter hardiness. [Rev. of: 

 Akerman, A., Hj. Johansson, and B. Platon. Jour. Swedish Seed Assoc, 1918.] Agric. 

 Gaz. Canada 6: 329-331. 1919— See Bot. Absts. 3, Entry 1380. 



2907. McBeth, I. G., and J. R. Allison. Recent investigations in orchard heating. 

 California Citrograph 4: 51, 65, 67. 5 fig. 1919— See Bot. Absts. 3, Entry 2346. 



RADIANT ENERGY RELATIONS 



2908. Goodspeed, Thomas Harper. Notes on the germination of tobacco seed, III. 

 Univ. California Publ. Bot. 5: 451-455. 1919. — The author finds that, contrary to statements 

 often made, the seed of the great majority of species of Nicotiana will germinate in darkness 

 as well as in light. He finds that seeds of 5 varieties of Nicotiana Tabacum, representing a 

 large proportion of the basic types from which the commercial strains of American tobaccos 

 have been derived, and of 5 varieties of N. rustica will germinate readily in darkness. He 

 found that in the majority of cases the number of both old and new seed germinated in dark- 

 ness was as great as, or more than, that germinated in continuous light. He found also that 

 seed may germinate in darkness slowly and scatteringly. He emphasizes the necessity of 

 properly controlled experiments in connection with such work. — W. A. Setchell. 



2909. Hurd, Annie May. Some orienting effects of lights of equal intensities on Fucus 

 spores and rhizoids. Proc. Nation. Acad. Sci. [U. S. A.] S: 201-206. 1919— Unilateral 

 illumination of sufficient intensity orients the first cleavage plane in certain plant spores, the 

 first cross wall being perpendicular to the direction of the light. To secure monochromatic 



