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came lo the same result and saw moreover that seeds which are exposed to very 

 small doses germinate faster than the control-plants; yet they are soon overtaken 

 and outstripped by the latter [Townsend 1897, p. 509, and 1899]. Burgerstein [1906, 

 p. 243] and KaufTmann [1899, p. 24, 40, 48] noted the same phenomenon. By 

 examining anatomically seedlings of Lupinus which had germinated in water that 

 contained ether Kaufmann saw that the sheath of sclerenchyma, which is normally 

 developed in seedlings without the leptome had not been developed. According to 

 the opinion of the author this phenomenon is to be attributed to a diminution of 

 the tissue-strains produced by the anaesthetization ' [loc. cit. p. 38]. Lately Schroeder 

 has found in experimenting with Avena-seedlings the same rules for the growth 

 as Elfving, Townsend e. t. c. found, i. e. that the growth is increased for a short 

 time in a weak atmosphere of ether while later it sinks beneath the normal growth; 

 large doses instantly arrest the growth of the plant [Schroeder 1908, p. 156 ff.]. 



Of great interest is the phenomenon, noted by Johannsen in 1893, that it is 

 possible through ether to diminish or suspend the resting-period of several seeds, 

 trees and bushes, a result which he had been led to through his extensive studies 

 of the periodic manifestations of life of the plants and which has occasioned a 

 great many investigations of this subject, probably owing to the great practical 

 interest attached to this phenomenon [Johannsen 1897, p. 33]. Suspension of the 

 resting-period may only be contrived at the beginning respectively at the end of 

 the resting-period but never in the mid of the resting-period: the reason of this 

 fact is yet unknown. If the resting-period is quite finished, the etherization has 

 no influence on the germination or may even arrest the germination [loc. cit. p. 27]. 

 Johannsen supposes that the suspension of the resting-period is owing to the 

 circumstance of the ether paralyzing the "growth-suspending power" possibly 

 affecting the growth as well [p. 49]. The dose adequate for this pui-pose varies 

 according to the different periods of rest; for instance in tulipa-bulbs it has been 

 noted that the optimal dose grows smaller towards the end of the resting-period 

 [p. 53]. It seems as if smaller doses of ether, used at proper periods cause an 

 acceleration of growth while larger doses produce a retardation [p. 54]. Later Aymard 

 fils [Aymard 1904] and Burgerstein [Burgerstein 1906] have made similar experiments 

 to investigate the shortening of the resting-period through ether and have arrived 

 at the same result. Also Behrens has succeeded in shortening the resting-period 

 of seeds through ether and instantly made them germinate. He suppose this 

 phenomenon to be caused by a stimulation, not by the dissolving through ether 

 of the waxy substances of the seed-coat and a subsequent accelerated absorption 

 of water [Behrens 1908, p. 538]. Eberhart regards the above mentioned theory 

 satisfactory in explaining the similar phenomenon of his own researches [Eberhart 

 1906, p. 56—58]. 



' Anna Bateson & Francis Darwin had previously proved that the tissue-strains are affected by 

 ether. They proved tiiat small doses increase the length of turgescent pith of growing shoots, when 

 the surrounding tissues have been removed; larger doses arrest it. [Bateson & Darwin, 1887]. 



