244 Varietäten, Descendenz, Hj'^briden. 



mesocotyl that permits deep planting and 2) the development of a 

 Single large radicle that rapidly descends to the moist subsoil and 

 supplies water during the critical seedling stage. CoUins believes 

 this type of maize to be suited to semi arid regions. 



Harshberger. 



Davis, B. M., The problem of the origin of Üenothera La- 

 rnarckiana De Vries, (New Phyt. XII. p. 233— 241. 1 textfig. 1913.) 



The author considers that the '' Oe)iotheva Lamarckiana''' of the 

 cultures of De Vries cannot be identified with the plant described 

 by Lamarck under the specific name grandiflora, which was sub- 

 sequently renamed by Seringe, Oe. Lamarckiana. He proposes, 

 however, that the plant used by De Vries shall retain the name 

 by which it is so well known, but that it shall be written Oe. La- 

 marckiana De Vries. He considers that there is little doubt that the 

 material of De Vries' cultures was derived, possibly greatly mo- 

 dified, from certain plants placed upon the market by Carter and 

 Company about 1860. A photograph is given of a herbarium sheet 

 in the Gra}'- Herbarium of Harvard University shewing an Oenothera 

 which may possibly have been not more than one or two genera- 

 tions removed from the original cultures of Carter and Co. The 

 author puts forward a plea for a persistent search through British 

 herbaria of the sixties of the last Century to see if further material 

 bearing on the subject can be obtained, and also through earlier 

 herbaria, to find evidence for or against the possibility of the pre- 

 sence of Oe. Lamarckiana De Vries in England, at dates previous 

 to 1860. Another problem on which research among herbarium 

 material may throw light is the question whether or not the Oe. 

 biennis described in the "English Botany" is the same form as the 

 Dutch biennis which probably represents the Oe. biennis o{ Linnaeus, 



Agnes Arber (Cambridge). 



Habenicht, B., Etwas vom Eteublatt. (Prometheus. XXV. p. 

 201-206. 9 A. 1913.) 



Mathematische Analysen fertiger und werdender Efeublätter. 



W. Herter (Berlin-Steglitz). 



Miller, R.. SchutzmitteldereinheimischenPflanzen 

 gegen die Angriffe der Tiere. (41. Ber. naturw. V^er. 

 Schwaben u. Neuberg. p. 25—95. Augsburg, 1913.) 



Eine kritisch gehaltene Schrift, welche alle Momente umfasst. 

 Es zeigt sich, dass nur selten bestimmte Schutzmittel an bestimmte 

 Pflanzenfamilien gebunden sind (z. B, Alkaloide für Solanaceen, 

 Bitterstoffe für Gentianeen). In anderen Familien herrscht dagegen 

 grosse Mannigfaltigkeit (bei Compositen: Stacheln, Wasserscheiden, 

 Haare, ätherische Oele, Milchsäfte; oder bei Flechten: Sclileim, 

 Säuren, flüchtige Stoffe). Mitunter tritt eine Häufung auf, z.B. bei 

 Oxalis acetosella: Gerbstofle, Feilborsten, Kaliumoxalat. In anderen 

 Fällen sind verschiedene Teile der Pflanze mit verschiedenen 

 Schutzmitteln ausgestattet. Schutzlos oder wenig ausgestattet sind 

 nur die Kulturpflanzen. Meist sind jene Organe am besten geschützt, 

 die am meisten des Schutzes bedürfen (Wurzelspitzen, Blüten); 

 auch tragwüchsige Pflanzen sind besser ausgestattet als Frühlings- 



