38 2 Messrs. F. Kidd, C. West, and G. E. Briggs. 



Table VIIE. — Eelatiou between Growth Eate and Eespiratory Activity. 









Ratio of 





Ratio of relative 



1 



1 



' Davs 



Relative 

 growth 

 rates. 







Kespi^ato^^■ 



relatire 



Eespivatorv 



^rowtli rate to 



1 J. Li^y Pikjuj^lOrt-l 



j from 



growth rate 



activity at 



respiratory 



mean 



■ geriiiina- 



index. 



to 



average field 





uCJLUJJCl oLih yxL (3 



tioii. 





respiratory 

 index. 



fceiiiperature. 



average iield 

 temperature 



1 in fiplfJ 



1 J.1J. \JHKj UKjl\A.t 



c 

 o 



lUo 



--■ --- 



9 -0*7 



U oDO 



4 oO 



i~» • *> o o 



lo '1 



. £i 



1 07 



o -oo 



n 'Qft 



u OO 



9 -07 



U .SbU 



lu O 



J. £7 



IDi 



^ iJ^ 



U OO 



O 0-* 



(\ •o'Tc: 

 U Zlt> 



17 D 







*> -fin 



U OO 



O / 





ID O 



33 



104 



1 -65 



0-63 



3 -09 



336 



16 -6 



40 



79 



1 -10 



0-72 



1 -58 



-500 



13 -6 



47 



81 



0-97 



0-84 



1 -03 



-496 



15 -4 



54 



45 



0-82 



-55 



1 -52 



0-296 



16 -6 



61 



34 



0-72 



-47 



0-94 



0-361 



12 -8 



72 



39 



0-63 



f)-62 



-97 



-402 



14-4 



82 



19 



0-53 



0-3G 



-90 



-211 



15-1 



89 



2i 





0-47 



0'62 



0-355 



12 -5 



100 



16 



0-38 



0-42 



-52 



0-308 



14-0 



114 



4-5 



0-32 



0-14 









It will be seen that while tlie relative growth rates vary over a wide range, 

 the ratio of the relative growth rate to the respiratory index remains fairly 

 constant throughout the life-cycle. In considering these ratios it should be 

 borne in mind that the values for the re.spiratory index and for the relative 

 growth rate are not strictly comparable for the following reason. Whereas 

 the values for the respiratory activity are maximal values for the temperature, 

 whether 10° C. or the average temperature of the field, the values for the 

 relative growth rate may not be, but may be limited by the operation of 

 uncontrolled factors, such for example as supply of carbohydrate or of 

 inorganic salts. 



In order to be strictly comparable, whether inter se or with the respiratory 

 activity, the values of the relative growth rate should be maximal, that is, not 

 limited. Further, the respiratory activity and the relative growth rate, both 

 being maximal at field temperatures, would be comparable throughout the 

 life cycle only if the effect of temperature upon the relative growth rate and 

 upon the respiratory activity were the same. In other words, for purposes of 

 strict comparison the respiratory activity and the relative growth rate should 

 not only both be maximal values but should both be determined at the same 

 constant temperature throughout the life-cycle. Since we do not know the 

 relation between temperature and growth the legitimacy of correcting the 

 respiratory index values determined at 10° C. up to field temperatures for 

 comparison with the relative growth rate is doubtful. As a result of this 

 correction, however, the ratio of relative growth rate to respiratory activity 

 at field temperatures is seen to vary with one exception inversely with 



