200 
C. West, G. E. Briggs, and F. Kidd. 
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le protoplasme et sur la nature de leur action toxique. 
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XIII. 53-86,1886. Abstract in Bot. Zeitung, p. 788, 1886. 
METHODS AND SIGNIFICANT RELATIONS IN THE 
QUANTITATIVE ANALYSIS OF PLANT GROWTH. 
By C. West, G. E. Briggs, and F. Kidd. 
T HE present authors are conducting a comprehensive study 
of the growth of Helianthus and are publishing (4) the results 
they have obtained from an analysis of the huge mass of data 
presented in the literature nearly half a century ago by Kreusler 
and his co-workers (7). It has been brought home to them very 
clearly in the course of this work that the previous attempts to 
express growth by some simplified formula are based upon a 
superficial similarity or upon wrong assumptions. 1 The effect of 
such generalisations has been to give an air of finality and to 
divert attention from the possibilities of deeper analysis. It is the 
formulation of methods for such an analysis that appears to us 
most urgent at present, and we have thought that it would be of 
interest to put forward at this stage the data and relations that 
seem to us significant. 
The Unit of Measure. 
In considering the problem of plant growth the plant physio¬ 
logist is faced with the question as to what unit of measure he 
shall adopt. From whatever point of view the growth of a plant 
1 For a more detailed consideration and criticism of these formulae the 
reader is referred to (4). 
