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which were still surrounded by bracts and entirely closed 

 and the top of which becamejust visible above the ground. 

 It appeared, however, that at this stage the stem on 

 which the flower is situated, had reached about its full 

 length and only grew a few millimètres more. The further 

 longitudinal growth, which is very considérable and brings 

 the flower above the ground, is nearly wholly caused by 

 the corolline tube between the ovary and the loose slips 

 of the perianth, Only to this stage I paid attention. Some 

 measurements of the corolline tube may follow: 



a. flower undamaged. 

 h. corolline lobes removed. 



c. corolline lobes, stamens and pistil eut away at 

 the upper end of the coalescent corolline tube. 



So removal of the terminal organs has not remained 

 without influence on the growth of the corolline tube, but 

 has not been able to check it to the same extent as in 

 the preceding cases. 



It deserves notice that removing the anthers and stig- 

 mas did not prevent the stamens and styles to reach about 

 their normal length. 



Summarising the investigation has shown that the nor- 

 mal longitudinal growth of the stem with Eranthis hiemalis 

 is only possible when the whorl of leaves at the top is 

 présent, while the flower exercises no influence on it. This 

 latter is also the case with the stem of Galanthus nivalis 

 and Narcissus Pseudo-Narcissus ; the flower-stalk however, 

 in thèse two plants, is checked in growth as soon as the 



