564 RESPIRATION AND FERMENTATION 



as for example at high temperatures, in compressed air, or in oxygenless 

 atmospheres 1 . 



Small doses of poison may cause a temporary increase in the rapidity 

 of growth, and hence also in that of respiration, although it has yet to be 

 determined whether more sugar is consumed than before in relation to 

 the crop produced. Similarly it is doubtful, whether the acceleration of 

 fermentative activity by traces of poisonous substance 2 (cobalt, fluorine, 

 chloroform, &c.) is due to more rapid growth and reproduction or to the 

 greater activity of the individual cells. Adult parts of higher plants react in 

 a somewhat similar manner, for Elfving and Lauren 3 frequently observed 

 that respiration was more active after treatment with ether or chloroform, 

 provided such treatment was not carried so far as to permanently injure the 

 plant. This reaction is unaccompanied by growth, but when etherization 

 awakens a plant from its winter rest 4 , the resumption of growth perma- 

 nently increases the total respiration. It has, however, not been found 

 possible to inhibit respiration entirely in turgid plants without death 

 ensuing, and hence it is all the more important to determine the accuracy 

 of Cl. Bernard's statement that alcoholic fermentation can be temporarily 

 inhibited by means of chloroform 5 , and if this be so, whether aerobic or 

 anaerobic respiration can be caused to undergo a similar temporary 

 suspension. 



Both growth and respiration are injuriously affected by any excessive 

 increase of respiratory or fermentative products (Sects. 77> 7^)- Higher 

 plants are usually injured by air containing 4 to 15 per cent, of carbon dioxide 

 (Sect. 57), and a still higher percentage exerts a depressing influence upon 

 many mould-fungi and bacteria 6 , whereas Saccharomyces and those bacteria 

 which normally grow in the presence of an abundance of carbon dioxide 

 are much more resistant. Fermenting yeast may generate a pressure of 

 twenty-five atmospheres in a closed vessel before the further production 

 of carbon dioxide is inhibited 7 , and those bacteria which may cause tins 



1 Maquenne, Compt. rend., 1894, T. cxix, p. 100. 



* First observed by Schulz, Bot. Zeitung, 1888, p. 610. See also Lintner, Handb. d. Landw. 

 Gewerbe, 1893, p. 238; Effrant, Compt. rend., 1894, T. cxix, pp. 254, &c. On the accommodation 

 to doses of poison, cf. also Sorel, ibid., 1894, T. cxvmj Dieudonne, Biol. Centralbl., 1895, Bd. xv, 

 p. 109. 



3 Elfving, Oefversigt af Finska Vetensk. Soc. Forh., 1886, Bd. xxvni; Lauren, Bot. Jahresb., 

 1892, p. 92. Detmer detected no such reaction (Landw. Jahrb., 1882, Bd. xi, p. 227); nor did 

 Bonnier et Mangin (Ann. d. sci. nat, 1886, vii. sen, T. nr, p. 16). 



4 Johannsen, Bot. Centralbl., 1896, Bd. LXVIII, p. 337. 



5 Cl. Bernard, Lefons s. 1. phenom. d. 1. vie, 1879, T. I, p. 276. 



6 Frankel, Zeitschr. f. Hygiene, 1889, Bd. v, p. 332; Frankland, ibid., 1890, Bd. vi, p. 13. 

 Additional literature by Lopriore, Jahrb. f. wiss. Bot., 1895, Bd. xxvni, p. 531 ; Fliigge, Mikro- 

 organismen, 1896, 3. Aufl., Bd. I, p. 445. 



7 Melsens, Compt. rend., 1870, T. LXX, p. 632. According to Lechartier and Bellamy (ibid., 

 T. LXXV, p. 1203^ and de Luca (ibid., 1876, T. Lxxxnr, p. 512;, fruits may generate a pressure of 



