It is therefore qui 4 J Voout any defi' lte mei 



t the temperature coefficient f o - - -re»s >as a certain 



value unless the corresponding temperature ranee is simulta- 

 neously stated. The coefficient value he e - "-- ••■ *" i 



ire and infinil -, depending or * peratur ran 



considered and v?c". the position of that . ' tal 



tern] range (hetween ' and rnaxj 



■ so-called van * t TToff rule, stati t the i ; - tui 3 co- 



ts of &a- sal reaction velcci' J ' r t val 



en 2.0 and 3.0 is obviously ' . i " 



> aonsidered, and this is trueof all ot 

 processes (whetherlbf i re tions cr not) only providing 



the processes have minimui and ture limits. 



It appears to Va true that many simple ^ v emicsl and physical 

 p>-- physiological processes also ->--_ 



ture coefficient values "between 2.0 and 3.0 fo»- vsrtair tempera- 

 ture ^pp88 within the ordinary r-are-e of weather temperatures 

 on the earth, and it is perhaps this fact that has led to so 

 much inadequate discussion ahout t v ese coefficients, especially 

 in physiological literature. Since the mathematical inter- 

 pretation of the concept of temperature coefficients has not 

 •hoen generally insisted <"*>-> ir +^?es discussiens, and sinrs t- 

 coefficient may have a constant cr nearly constant value for a. 

 considerable ranee o r temperatures within the limits of what 

 ■e commonly known ftp ordinary temperatures, t v <* coef ml 



i-ss frequently been ragarded as a constant for t v '« process con- 

 sider-^, without any specific reference to the temperature range 

 rtferre* to. Eut van ' t "off and the other writers on tbi 

 subject have all been perfectly well aware that +>e value of 



