34 The Unity of the Organism 



In fundamental principle the one is no more and no less 

 acceptable than the other. 



Any half plausible suggestion that a particular minute, 

 obscure part of the germ-cell may be a "bearer of heredity" 

 seems to endow that part with a peculiar fascination to biol- 

 ogists who haA'e the elementalist habit of thinking, and this 

 secures to it an inordinate attention until the untenability 

 of the hypothesis is so overwhelmingly proved that even the 

 most credulous are forced to abandon it. 



Several biologists have recognized something of the state 

 of mind here indicated without, however, perceiving its real 

 meaning. Thus in a review of the work of Meves, which 

 will be examined presently, we read: "the new interpretation 

 which Meves gives at this time indicates that many are 

 still dissatisfied with the all-sufficiency of the [nuclear] 

 theory, and are eagerl}^ seeking and grasping, as it were, 

 the first visible sign of any other substance which may serve 

 to carry the hereditary qualities." ^ The remark to be 

 made about any statement of this kind is that the real 

 though usually unperceived ground of dissatisfaction is not 

 with the all-sufficiency of the nuclear theory of heredity, but 

 with the all-sufficiency of any theory that attempts to local- 

 ize the function of carrying heredity in some small, specific 

 fraction of the germ-cells ; and that the attitude which 

 Doctor Payne well characterizes as "eagerly seeking and 

 grasping" which has marked so much of recent search after 

 the physical basis of heredity, has a large measure of genu- 

 ine illusion in it. Inspired by the ages-old, alluring belief 

 that an imperceptible final cause and explanation is hidden 

 somewhere within or behind whatever is grossly sensed, the 

 pursuit becomes "eager and grasping," which is another 

 way of saying that it becomes more or less irrational and 

 fitful. 



The truth of these remarks is rather strikingly exempli- 

 fied in the short, somewhat feverish history of the mitochon- 



