SPECIAL CASES 601 



Similar phenomena are observed when old evergreen leaves die, but these 

 apparently do not function to any marked extent as storage receptacles 

 during winter l . Owing to the rapidity with which the assimilatory products 

 are translocated, leaves prematurely killed by summer-drought do not 

 contain an unusually large amount of organic material ' J . 



Fruits and seeds. The large quantities of organic food necessary for 

 the formation of the fruit and seed are either entirely or for the most part 

 conveyed from the assimilating organs. Even in the most highly chloro- 

 phyllous fruits the amount directly assimilated is comparatively small and 

 is moreover not absolutely necessary, for grapes attain their full development 

 when the inflorescence is kept in darkness after the flowers have been 

 fertilized". 



The food-materials are conveyed to the developing ovule mainly 

 or entirely through the funicle, but the growing embryo probably often 

 absorbs food through its entire periphery, and in many cases displaces 

 and consumes the preformed endosperm tissue. The development both 

 of the fruit and seed follows as the direct consequence of fertilization, 

 and the resulting translocatory activity usually continues until the ripening 

 is complete and may not immediately cease when an unripe inflorescence 

 is removed from the parent plant 4 . Marked metamorphoses may occur 

 during the final stages of development, and thus when unripe seeds of 

 Paeonia are removed from the carpel, the accumulated starch is replaced 

 by fatty oil, while apples picked when unripe still undergo metamor- 

 phoses characterized by changes of colour and taste 5 , the latter being 

 partly due to a diminished acidity and partly to an increased percentage 

 of sugar. It is, however, doubtful whether the acids are neutralized or 

 decomposed, both of which are possible. Indeed according to Porteie 6 



many plants before the fall of the leaf, but it does not necessarily follow that the sugar produced is 

 also removed.] 



1 E. Schulz, Flora, 1888, p. 223 ; Lidforss, 1. c. 



- Cf. G. Kraus, Bot. Zeitung, 1873, p. 401. On translocation in perianth leaves, cf. L. Miiller, 

 Vergl. Anat. d. Blumenblatter, 1893, p. 296. 



3 Muller-Thurgau, Bot. Jahresb.. 1877, p. 815. Cf. also Sachs, Bot. Zeitung, 1865, p. 117. On 

 the decomposition of carbonic acid by fruits, and the gradual decrease during ripening, cf. Ingenhousz, 

 Versuche mit Prlanzen, 1786, Bd. I, p. 72 ; Bd. II, p. 233 ; Saussure, Rech. chini., 1804, pp. 57, 129, 

 and Ann. d. chim. et d. phys., 1821, T. XIX, p. 158; Berard, ibid., 1821, T. LXXVI, pp. 152, 225_; 

 Fremy, Compt. rend., 1864, T. LVIII, p. 656 ; Cahours, ibid., pp. 495, 653, &c. 



4 Cf. Sect. 107 for the after-ripening of cereals. [Also Schmid, Ban u. Function d. Grannen 

 unserer Getreidearten, Bot. Centralbl., Bd. LXXVI, 1898, p. i.] 



5 On the decomposition of chlorophyll in fruits, cf. G. Kraus, Jahrb. f. wiss. Bot., 1872, Bd. vin, 

 p. 131 ; Millardet, Bot. Zeitung, 1876, p. 733; Schimper, Jahrb. f. wiss. Bot., 1885, Bd. xvi, p. i. 

 Paeonia, Pfeffer, ibid., 1872, Bd. vin, p. 510. 



6 Porteie, Bot. Jahresb., 1879, P- 2 9 > Erlenmeyer, quoted by Liebig, Die Chemie in Anwend. 

 auf Agric., &c., 1876, 9. Aufl., p. 30, footnote. [C. Gerber (Ann. d. sci. nat., iv, 1897, pp. 1-280) 

 states that during the ripening of fleshy fruits citric and tartaric acids decompose at 30 C., malic at 



