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Bot Zeiting 1873 Zur Frage über Transversal-geotropism & -Heliotropismus

3 articles. p. 17 —A. B. Frank— allude to as very interesting articles; after his Book.—

p. 37 different intentions of light act differently on the stems of plant

p. 50 Leaves which are horizontal in day — placed in darkness— in many many cases bend more or less upwards.— Refer to p 262 of De Vries in support

(Whole paper seems to me conclusive)

[Movement in plants, p. 438: "Transversal-heliotropismus (of Frank*) or Diaheliotropism.—The cause of leaves placing themselves more or less transversely to the light, with their upper surfaces directed towards it, has been of late the subject of much controversy. We do not here refer to the object of the movement, which no doubt is that their upper surfaces may be fully illuminated, but the means by which this position is gained. Hardly a better or more simple instance can be given
* 'Die natürliche Wagerechte Richtung von Pflanzentheilen,' 1870. See also some interesting articles by the same author, "Zur Frage über Transversal-Geo-und Heliotropismus," 'Bot. Zeitung,' 1873, p. 17 et seq."]