-17- 



series, the quotient just mentioned is to be divided by the 

 exact ntuiiber of hovrrs elapsed since the starting of the 

 cultures in each case, thus giving the mean hourly rate of 

 shoot elongation for the given culture. Subtracting the 

 total elongat ion value for the shorter period (2, above) 

 from the corresponding value for the lohger period (4, above^ 

 gives a number representing the total shoot elongation for 

 the last portion (about 24 hours) of the whole culture period. 



Each of the six different series (each series 

 corresponding to one of the six solution types and each 

 including the seven different temperatures) was repeated 

 once, excepting in the case of the lowest temperatiH'e, so 

 that the data obtained refer to the first or second test 

 for each series, excepting those for 13° C. 



• Viability , grov/th rate . a nd solution composition * 

 Forty-tv;o tables of data weie obtained from these 6 solu- 

 tion types, tested at 7 different maintained temperatures. 



Only table I, giving the results obtained from the solutions 



in this 

 of type I tested at 31° C, is giv-en/papei; it is presented 



as an illustration of the results obtained at the end of 



the culture period (3 and 4, alcove.). The two halves of 



the table represent the tv; o like tests for the solutions 



or sets of salt proportions, 

 of type I and for 31° C. -^'he solutioni^are designated 



by the symbols in the first column, these teiag Repeated fbr the 



tes t as the data are here tshul- ted. 

 secbnd/ Each rue an hourly rate of shoot elongation is obtained 



