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material was not entirely derived from the sandy soil, yet 

 ail thèse plants were in less favourable nutritive conditions 

 than the plants on the manured soil. So the experiments 

 will show us the conséquences of the différence in nutrition. 



For investigation I chose some characters that are 

 easily expressed quantitatively and numerically and took 

 care that the détermination was made at the same time 

 for both cultures and that the same parts of both were 

 always taken. 



In this way I determined in the flrst place the length 

 of the leaf of Ibei'is amara. In .July the length of the five 

 oldest leaves, which were already adult then, was measured. 

 Besides, in the autumn, after the plants had been dug out, 

 the length of the plant was determined from the base to 

 the top of the inflorescence of the principal stem; at the 

 same time were counted the number of branches of the 

 second order, the number of branches of the third order 

 and the number of fruits on the inflorescence of the 

 principal stem. 



Oï Malva vulgaria the number of akènes of the schizocarp, 

 the length of the leaf-blade and the length of the leaf-stalk 

 were determined. Thèse countings and measurements were 

 made in the beginning of July, when a very distinct 

 différence in the devclopment between the two cultures 

 was visible, hence probably before the roots of the plants 

 on the meagre soil had penetrated the layer of sand and 

 in any case before a better nutrition had any perceptible 

 effect. 



In the case of Anethum graveolens and Scandix Pecten- 

 Veneris the number of lobes of the flrst leaf was counted 

 in the plants that had survived in germinating dishes. 

 Besides I determined in adult plants of Scandix Pecten- 

 Veneris the number of umbel-rays and with Anethum 

 graveolens also the number of umbel-rays and at the same 

 time the number of flowers of the umbellet. For the 



