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Indiana University Studies 
bases, or equally on both bases; and it seems possible to rec- 
ognize species of Cynips that have originated by physiologic 
as well as morphologic mutation. This seems reasonable, for 
organisms inherit their psychologic and physiologic characters 
in the same sense as they inherit their morphologic struc- 
tures. As a matter of fact, the materials transmitted from 
one generation to the next are neither morphologic nor physi- 
ologic characters but an initial bit of simple protoplasm and 
a physico-chemical organization which will direct the activi- 
ties of that protoplasm. Many outside, environmental factors 
also affect the developing organism, but the final form of the 
plant or animal is inherited in the sense that the inherited 
genes exert the primary influence on that form. It is in pre- 
cisely the same sense that the physiologic or psychologic char- 
acters of species may be said to be inherited. There seems no 
sound basis for the oft-made suggestion that physiology is a 
function of structure — or structure of physiology. It would 
appear that both are products of the same protoplasm and are 
controlled by the same hereditary mechanism. 
