FURTHER STUDIES ON THE INTERRELATIONSHIP 
OF MORPHOLOGICAL AND PHYSIOLOGICAL 
CHARACTERS IN SEEDLINGS OF 
PHASEOLUS! 
J. ARTHUR HARRIS 
Station for Experimental Evolution, Cold Spring Harbor, N. Y. 
INTRODUCTORY REMARKS 
In a series of papers published during the past several years I have 
emphasized the importance of investigations of the relationship be- 
tween the morphological and the physiological characteristics of the 
organ and of the organism. 
The structural variations of the organs of which the organism is 
made up are the resultant of intrinsic and extrinsic factors—of heredity 
and environment, or of nature and nurture. Morphogenetic processes 
must, therefore, be investigated by physiological methods, and be 
interpreted in physiological, and ultimately in physical and chemical, 
terms. 
The purpose of this paper is to supplement and extend the results 
of an earlier study? in which it was shown that in bean seedlings char- 
acterized by certain morphological variations from type, the develop- 
ment of primordial leaf tissue is less than in normal controls grown 
under conditions as nearly as possible identical. The data then 
available indicated that a reduction of the volume of primordial leaf 
tissue is associated with abnormalities of all the types studied, but 
that the type of variation influences, in some degree, the amount of 
reduction. 
In these first experiments the conclusions were based on primordial 
leaves only. 
The use of such leaves has the obvious disadvantage that they 
are completely formed in the seed, and undergo merely an enormous 
expansion (and an undetermined amount of differentiation) in the 
1 Studies on the Correlation between Morphological and Physiological Char- 
acters, V. Studies I-IV of the series are to be found in Genetics I: 185-196. I916; 
2eeto—2i2. OL 72 a2o2—-2008) TOL 7: 
2 Harris, J. Arthur. Studies on the Correlation of Morphological and Physio- 
logical Characters: The Development of the Primordial Leaves in Teratological 
Bean Seedlings. Genetics 1: 185-196. Ig16. 
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