Ill] THE EFFECT OF TEMPERATURE 111 



The mile and the hundred yards are won by different runners ; 

 and maximum rate of working, and maximum amount of work 

 done, are two very different things*. 



In the case of maize, a certain series of experiments shewed that 

 the growth in length of the roots varied with the temperature as 

 followsl : 



Then choosing two values out of the above experimental series 

 (say the second and the second-last), we have / = 23-5, n = 10, 

 and F, F' = 10-8 and 69-5 respectively. 



69'5 

 Accordingly YrTo = 6-4 = x^^. 



Therefore ^f^ ' ^^ '^^^^ = ^°g ^• 



And, X = 1-204 (for an interval of 1° C). 



This first approximation might be considerably improved by 

 taking account of all the experimental values, two only of which 

 we have as yet made use of ; but even as it is, we see by Fig. 26 

 that it is in very fair accordance with the actual results of 

 observation, within those particular limits of temperature to which 

 the experiment is confined. 



* Cf. Errera, L., UOptimmn, 1896 {Rec. d'Oeuvres, Physiol, generate, pp. 338-368, 

 1910); Sachs, Physiologie d. Pflanzen, 1882, p. 233; Pfeffer, Pftunzenphysiologie, 

 ii, p. 78, 1904; and cf. Jost, Ueber die Reactionsgeschwindigkeit im Organismus, 

 Biol. Centralbl. xxvi, pp. 225-244, 1906. 



t After Koppen, Bull. Hoc. Nat. Moscou, xliii, pp. 41-110, 1871. 



