THE METAZOA 



vious settled layer of stones, a mistake 

 which is not uncommon. Hence Darwin, 

 when he found himself confronted by this 

 special problem, ten years after he pub- 

 lished his book on the 'Origin of Species, 

 propounded a theory to which he gave the 

 name of Pangenesis. 



This pangenesis postulated a well-nigh 

 infinite number of small gemmules, 

 which are given off by every cell in the 

 body and which make their way to the 

 primal microscopic dot, so that this con- 

 tains a representation of every part of 

 the parent body. But as a man who had 

 lost his right leg would have no right leg 

 gemmules to send thereafter, so a child 

 born to him after his accident would be 

 minus that leg. This and similar con- 

 siderations led Darwin finally, with char- 

 acteristic candor, to pronounce this theory 

 " unfortunate." 



Since Darwin, or at least for thirty years 

 101 



