NOTES AND ABSTRACTS. 



699 



Ichang, Hupeh, by Dr. Henry, but it has been introduced into cultivation 

 by Mr. E. H. Wilson. It is a perennial plant, nearly allied to the Fox- 

 gloves ; it grows to a height of from 1 to 3 feet, with purplish flowers 

 growing in racemes. — G. S. S. 



Report on the Suc3ess of Plants Contributed from the Royal 

 Botanic Garden in Berlin to the Botanical Garden in Victoria. 



By Dr. S trunk (Not, Konig. Bot. Berlin, Bd. IV., pp. 46-58 ; July 10, 

 1903). — Includes varieties of Cocoa, Kola, Coffee, Tea, Caoutchouc plants, 

 Vanilla, Fibre plants, &c, and notes on their growth and success 

 generally. — H. 31. W. 



Restrepia antennifera.— By W. B. Hemsley (Bot. Mag. tab. 7930). 

 Nat. ord. Orchidacece, tribe Epidendrece. Native of Colombia. Stems 

 clustered, 6-8 inches high. Flowers 1-3 on each stem, 2^ inches across, 

 striped with dark purple on a whitish ground. — G. II. 



Rhythm in Plants, On the Artificial Production of. With a 

 Note on the Position of Maximum Heliotropic Stimulation. By Francis 

 Darwin and Dorothea F. M. Pertz (Ann. Bot. vol. xvii. No. lxv. p. 94 ; 

 Jan. 1903). — That parts of plants can acquire a habit of periodic move- 

 ment, so that the same periodic movement continuss when the original 

 stimulus has b3en withdrawn, is one of the most wonderful of plant 

 phenomena. " In the Annals of Botany, October 1902 (vol. vi. p. 245), 

 we described a series of experiments on this subject. We remarked (p. 

 259) that ' Those who repeat our experiments must not expect uniform 

 success, as there is undoubtedly a certain capriciousness in the results, 

 which probably depends on varying degrees of vigour in the plants used.' 

 The present research was begun in the hope of discovering a cause for this 

 capriciousness ; in this we have been disappointed ; nevertheless, some of 

 our results seem worth printing. The fundamental experiment consists 

 in subjecting se3dlings or growing shoots to a series of opposite 

 stimuli following each other at equal intervals of time. The stimuli 

 may be due to gravitation or to light ; in either case they tend to 

 produce curvatures in two opposite directions. It might be supposed that 

 the result would be an absence of all curvature. But this is not so ; what 

 happens is that the plant curves first in one and then in the opposite 

 direction ... In our former experiments the reversal of the stimulus 

 occurred at intervals of half an hour ; we have now succeeded in building 

 up a periodic movement in a fifteen-minute rhythm. That during the 

 continuance of the alternate stimuli a plant should nutate in a given 

 rhythm is sufficiently remarkable, but it is far more interesting that the 

 rhythm should continue after all stimulation has ceased, and this we 

 again find to be the case. We have again used the intermittent klinostat. 

 employing, of course, a horizontal axis for geotropic experiments, and a 

 vertical axis in the case of heliotropism . . . The act of rotation is 

 rendered gentle by a fan-governor, so that the plant is not unduly jarred." 



The subjects used in the experiments recorded are Mustard seedling 

 (geotropism), cut stalks of a Valerian (geotropism), seedlings of Phalaris 

 canaricnsis (heliotropism), and seedlings of Oat (heliotropism). Of Phalaris, 



