98 



"four inseparable factors of evolution" (heredity, ontogeny, 

 environment, and selection). Macfarlane rejects ontogeny as a 

 cause or factor in evolution. 



In accepting the hypothesis "that living and non-living bodies 

 are alike irritable" (p. 44), no reference is made to Bose's full 

 development of that idea in his Response in the Living and Non- 

 living, and other writings. 



On page 81 "inert ether particles" are referred to as forming 

 "the centers of the atomic and molecular structures." No 

 reference is here made to the electron theory of atomic structure, 

 which regards the atom as, in figurative sense, a miniature "solar 

 system," with negative electrons moving in orbits around a 

 nucleus of positive and negative electrons — chiefly positive. This 

 hypothesis, based upon studies in radioactivity and related in- 

 vestigations, has been the one in most general favor with physi- 

 cists for a decade or so. Attention may also be called here to a 

 present tendency of some physicists to question the older con- 

 ception of a universal elastic ether, in light of the theory of 

 relativity, which originated in the famous experimentum crucis 

 of Michelson and Morley (1887) to obtain evidence of an ether 

 drift." In fact, a physicist friend has assured the reviewer that 

 the expression "inert ether particles" does not convey any 

 meaning to a physicist. 



Adhering to the energy point of view, and the point of view of a 

 granular or atomic ether, protoplasm is defined (p. 86) as "a 

 definitely correlated rotatory motion of variously energized 

 (or linked) and highly complex groups of ether particles of col- 

 loid nature, in which the specific rates of motion between the 

 groups are an expression of biotic energy." This would seem to 

 define protoplasm as a mode of motion rather than as a substance. 

 In harmony with this conception, life is defined (p. 97), as 

 "Relatively similar complexity and synchronism of motion of 

 quinary, hexary, and heptary compounds, that represent similar 

 complex definiteness of structure and similar lines of flow of 

 biotic energy." 



The different tropisms shown "by living organisms depend each 

 upon a special class or kind of plastids or energids which "show a 



