50 Botanisches Centralblatt. 



Merkmale der Periodizität der Wurzel, sowie über die Verbreitung: 



der Metakutisierung der Wurzelhaube im Pflanzenreich. (Festschr. 



100 jähr. Best. kgl. württemb. landw. Schule. Hohenheim. 1918. p. 



129-151.) 

 Robertson, C. 1918. Pollination of Asclepias ciyptoceras. (Bot. Gaz. 



LXVL p. 177.) 

 Speck, J. 1918. Oberflächenspannungsdifferenzen als eine Ursache 



der Zellteilung. (Heidelberg, 1918. 8». 83 pp. 21 F.) 

 Stewart, F. C. 1918. Tubers within tubers of Solanum tuberosum.- 



(Brooklyn bot. Card. Mem. I. p. 423—426. 3 f.) 

 Tammes, T. 1918. Die Flachsbiüte. (Rec. Trav. bot. neerland. XV. p. 



185-227. 22 F.) 

 Weatherwax, P. 1918. Improved technique for corn pollination. (Proc. 



Indiana Ac. Sc. 1917 [1918]. p. 105-107. 2 f.) 

 Weniger, W. 1918. Fertilization in Lilium. (Bot. Gaz. LXVL p. 259— 



268. 3 pl.) 



V. Varietäten, Descendenz, Hybriden. 

 Cf. II. ßaiiey and Tupper; IV. Meyer. 



Andrews, E. F. 1918. Adaptation and natural selection. (Bot. Gaz. 



LXVL p. 382.) 

 Cunningham, B. 1918. Cross-conjugation in Spirogyra Weberi. (Bot. 



Gaz LXVL p. 272-273. 1 f.) 

 Davis, B. M. 1918. The segregation of Oenothera brevistylis from 



Grosses wiih Oenothera Lamarckiana. (Genetics. IlL p. 501—533.) 

 Kajanus, B. 1918. Kreuzungsstudien an Winterweizen. [V. M.]. (Bot.. 



Not. 1918. p. 235—244.) 

 Kajanus, B. 1918. Ueber eine konstante gelbbunte Pisum Rasse. (Bot. 



Not. 1918. p. 83-84.) 

 Kajanus, B. 1918. Ueber eine Kreuzung zwischen zwei Typen von 



Sommerweizen. (Bot. Not. 1918. p. 245—247.) 

 Ness, H. 1918. Hybrids of the live oak and overcup oak. (Journ. of 



Heredity. IX. p. 263-268. 3 f.) 

 Safford, W. E. 1918. Cosmos sulphureus, the xochipalli or flower 



paint of the Aztecs. (Journ. Washington Sc. VIIL p. 613—620. 2 f.) 

 Schmidt, J. 1918. Investigations on Hope (Humulus lupulus L.). XI: 



Can different clones be characlerised by the number of marginal 



teeih in the leaves? (C. R. Labor. Carlsberg. 1918. 24 pp. 1 f.) 

 Shamel, A. D. 1918. A dry bloodorange strain. (Journ. of Heredity. 



IX. p. 174-177. 2 f.) 

 Shamel, A. D. 1918. Why navel oranges are seedless. (Journ. of 



Heredity. IX. p. 246-249. 2 f.) 

 Shamel, A. D. 1918. Some variable ears of dent corn. (Journ. of 



Heredity. IX. p. 29—32. 4 f.) 

 Shamel, A. D. 1918. Striking orange bud variations. (Journ. of Here- 

 dity. IX. p. 189—191. 2 f.) 

 Shamel, A. D. and C. S. Pomeroy. 1918. A fruiting orange thorn. 



(Journ. of Heredity. IX. p. 315-318. 2 f.) 

 Shull, G. H. 1918. The duplication of a leaf-lobe factor in the shep- 



herd's purse. (Brooklyn bot. Gard. Mem. I p. 427—443. 4 f.) 

 Sinnott, E. W. 1918. Isolation and specific change. (Brooklyn bot. 



Gard. Mem. I. p. 444—447.) 

 S6, M. and Y. Imai. 1918. On the Xenia in the barley. (Bot. Mag. 



Tokyo. XXXII. p. 205—214.) 

 Stomps, T. J. 1918. Vergrünung als parallele Mutation. (Rec. Trav. 



bot. neerland. XV. p. 17-26. 1 F. 1 T.) 



