NE W PO WER OF NE W CENTRES. 



295 



during the early periods of development of every vertebrate 

 animal, which apparently only serve the purpose of giving 

 origin within themselves to other centres^ from which the 

 bioplasts, which are to take part in the actual formation of 

 tissues, are at length developed. Thus, many successive 

 series of masses of bioplasm are formed, centre within centre, 

 and are succeeded by new ones before those by the agency 

 of which the tissue or organ is to .be formed result. But 

 while, as I have stated, each successive series of bioplasts 

 seems to have acquired new power, there are no characters 

 by which any could be distinguished from the preceding or 

 succeeding series. That there is a difference is, however, 

 proved by the difference in the results of living ; but the 

 most minute examination that could be made would not 

 enable any one to predicate what these results would be, or 

 even to distinguish the formative bioplasm from a form that 

 was altogether destitute of structure-forming power. 



At the same time that the new centre acquires new 

 powers, it retains by inheritance some of those possessed by 

 the bioplasm that preceded it, and transmits these to the 

 new centres which originated in it, and are to succeed it. 

 It would appear more in accordance with the facts to con- 

 clude that the powers exhibited by the last of a series of 

 masses of bioplasm had been retained in a dormant state, 

 as it were, in relation with the matter of every one of its 

 predecessors, and thus that power-producing power was 

 handed down from one generation of material particles to 

 another, than to assume that the new powers were acquired 

 as the process of evolution of centres took place. Nor is 

 there ground for supposing that the newly-acquired powers 

 result from the change in external conditions to which the 



