i66 METABOLISM 



Green. 1901. Die Enzyme. German edition by Windisch. Berlin. 



Griessmayer. 1897. Die Proteide d. Getreidearten. Heidelberg. 



Grubler. 1881. Journ. f. prakt. Chem. 131, 97. 



[Herissey. 1903. Rev. d. Bot. 15, 345.] 



Hildebrand. 1884. Lebensverhaltnisse d. Oxalisarten. Jena. 



HoLLE. 1877. Flora, 60, 113. 



[IwANOFF. 1902. Ber. d. bot. Gesell. 20, 366.] 



Jentys. 1892. Bullet. Acad. d. Cracovie. 



KoNiG. 1882. Chem. Zusammensetzung d. menschl. Nahrungsmittel. Berlin, 



[Leclerc du Sablon. 1905. Rev. d. Bot. 16, 341.] 



Medicus. 1803. Pflanzenphysiol. Abhandlungen, 2, 140. 



Mohr. 1902. Centrbl. Bakt. II. Abt. 8, 601. 



Neumeister. 1894. Zeitschr. f. Biol. 30, 447. 



Newcombe. 1899. Annals of Botany, 13, 49. 



[PosTERNAK, 1903. Compt. rend. 137, 202, and 1905, 140, 322.] 



PuRiEWiTSCH. 1897. Jahrb. f. wiss. Bot. 31, i. 



Sachs. 1859. Bot. Ztg. 17, 177 (Ges. Abh., i, 557). 



[ScHELLENBERG. 1905. Ber. d. bot. Gesell. 23, 36.] 



Schmidt. 1891. Flora, 74, 300. 



ScHMiEDEBERG. 1 877. Zcit. f. physiol. Chem. i, 205. 



Schroder. 1901. Bot. Centrbl. Beihefte, 10, 122. 



ScHULZE. 1882. Versuchsstationen, 27, 357. 



ScHULZE. 1890-2. Zeit. f. physiol. Chem. 14, 227 ; 16, 387. 



Shorey. 1897. Cited in Revue gen. de Bot. 1902 ; 14, 283. 



SiGMUND. 1890-92. Cited by Green, 1 90 1. 



Tschirch. 1900. Ber. d. pharm. Gesell. 10, 214. 



Vines. 1891. Annals of Botany, 5, 409. 



[Vines. 1905. Ibid. 19, 171.] 



Weyl. 1877. Zeit. f. physiol. Chem. i, 72. 



WORTMANN. 1890. Bot. Ztg. 48, 58 I. 



WuRTZ. 1879. Compt. rend. 89, 425. 

 Zaleski. 1902. Ber. d. bot. Gesell. 20, 426. 

 [Zaleski. 1905. Ibid. 23, 133.] 



LECTURE XIV 



THE CONVERSION OF THE PRODUCTS OF ASSIMILATION. Ill 



THE TRANSLOCATION AND TRANSFORMATION OF DISSOLVED RESERVES 



The reserves accumulated in storage organs become at definite times 

 mobile, that is to say, they are transformed from an insoluble and non-diffusible 

 into a soluble and diffusible state. The object of this transformation is to 

 permit of these substances migrating from cell to cell, and such translocation 

 of material from the storage regions to the places where they are used up 

 is a phenomenon of wide occurrence in the plant. It is very easy to prove the 

 migration of carbohydrates out of the foliage leaf, and much research has been 

 carried out on this subject. One can often observe that a leaf which is full 

 of starch in the evening has become quite empty of starch next morning, after 

 a warm night, if it remains attached to the plant, but that if it be cut off, the 

 amount of carbohydrate suffers but little change during the night. We may, 

 therefore, conclude that a migration of carbohydrate takes place out of the 

 normal leaf in the dark. This migration does not cease, however, by day. 



It is more difficult to prove the migration of nitrogenous substances from 

 the foliage leaf. Exact research on this subject is as yet not forthcoming. 

 KosuTANY, it is true (1897), has made careful comparative researches on the 

 amount of nitrogenous substance present in vine leaves in the afternoon and in 

 the morning before sunrise, but unfortunately he based his calculations on 



