370 'Journal of Comparative Neurology and Psychology. 



compounding diverse elements representing all organs or charac- 

 ters to be inherited, as seemed to be implied in the gemmule and 

 like hypotheses. He says: "Diese unendliche Mannigfaltigkeit 

 ist in winzigen Tropfehen von Idioplasma virwirklicht welche 

 durch das Mikroskop, durch chemische und physikalische Hilfs- 

 mittelnicht von einander zu unterschiedensind. An der Keiman- 

 lage selber ist nicht die Masse, sondern nur die Beschaffenheit 

 seiner kleiner wirksamen Partie von Idioplasm das entscheidende 

 * * '''. " But he goes on to state that the structure of idioplasm 

 is determined by its molecular composition, particularly by the 

 arrangement of the micellae with the motions and forces peculiar 

 to them. 



For us the structure is but a partial revelation of the equili- 

 brated status of these "peculiar motions and forces." When tvs^o 

 types of activity (motion) fuse they form a resultant which is dif- 

 ferent from either and is by no means an algebraic sum of both. 

 When oxygen and hydrogen unite the result is not an algebraic 

 sum of the qualities (activities) of oxygen and hydrogen but a new 

 quality-complex unlike either and represented by its own locus 

 formula. In like manner, when two heredity bearers unite in a 

 germ cell the resultant is not an algebraic sum of the two formulae 

 but a new figure. Again, water, under certain circumstances, 

 can be decomposed, as we say, into oxygen and hydrogen, i. e., 

 the composite movement to which the water molecule owes its 

 existence can be resolved into the original two simpler modes. 



In like manner, while the germ cell does not contain discrete 

 elements corresponding to the various organs of the future body, 

 it does contain in its complex trajectory elements which under 

 appropriate conditions and with the cooperation of certain external 

 forces or constants may give rise to all of the coordinated activi- 

 ties constituting the organs of the complete organism. 



So difficult is this conception that we venture to remind the 

 reader of the simple illustration afforded by compound harmonic 

 traces. In the trace produced, e. g., by a mirror attached to a 

 tuning fork we have the direction of motion in one plane represented 

 by a straight line, the movement in the other plane at right angles to 

 it represented solely by variations in rate of the spot of light which 

 generates the trace. In other words, the harmonic nature of the 

 trace does not appear in the line of light generated by the mirror 

 but is only a question of the law of the motion of the generating 



