by Green Plants from certain Organic Compounds. 165 

 B. Supplied to the Roots. 



Solution used. 



Plants. 



Eeeults. 



The culture solution 

 + 0*5 per cent, 

 glycerin 



Phaseolus vulgaris 

 Acer pseudoplatanus 

 Qitercus rohur 

 Campanula glomerata 



All formed starch after 

 5 days. 



In a second series of experiments with the same solution as above 

 I found that — 



Cheiranthus Cheiri — 



A. 2 plants 



B. 1 plant 



C. 3 plants 



Had formed starch 

 after 48 hours - 



„ 60 „ 



Acer pseudoplatanus- 



A. 1 plant .... 



B. 3 plants. . . . 



68 

 74 



From time 

 of placing 

 )> in the cul- 

 ture solu- 

 tion. 

 I 



For experiments with Acer pseudoplatanus, L. in solutions with 

 varying amounts of glycerin, I found that no starch was formed when 

 the solution was stronger than 10 per cent, glycerin,* and solutions 

 15 — 20 per cent, glycerin decidedly injured the plant in twelve hours, 

 and ultimately caused its death. 



The same results are obtained with other plants, e.g., Quercus rohur 

 and ~Eup}iorbia helioscopia, as with Acer pseudoplatanus, L. 



No. 6. Experiments with Lcevidinic Acid. 



The acid was prepared from the laavulose obtained by Kiliani'sf 

 process from commercial inulin. 



The laevulose is boiled with dilute sulphuric acid, and the zinc salt 

 of laevulinic acid obtained from the product by the process recom- 

 mended by Grote and Tollens.J 



The ethyl ethereal salt was then obtained by decomposing the 

 alcoholic solution of zinc salt with H 2 S, filtering off the ZnS, boiling 

 to expel H 2 S, saturating with HC1, and distilling in the usual way. 



* As A. Meyer states that leaves form starch when placed in 10 per cent, solu- 

 tions of glycerin, it must be assumed that the root tissues are affected in these 

 experiments, or that such strong solutions are unable to travel from the root to 

 leaves. 



f See Kiliani in { Liebig's Annalen/ vol. 205, 1880 ; and also in * Berichte 

 Deutsch. Chem. G-esell.,' 1880, p. 2426. 



% ' Liebig's Annalen,' vol. 175, 1875, and vol. 206, 1881. 



