Darwin 28 1 



Of Darwin's pangenesis it is necessary here to men- 

 tion only the conception that the sexual or reproductive 

 organs in general were not so much the place of refuge to 

 which the germ plasm withdrew immediately after its 

 separation from the soma at the very commencement of 

 development, as rather the containers of the germinal 

 substance continually produced and secreted by other 

 parts of the organism lying without these organs, so that 

 they build up as it were the sexual or reproductive 

 cells out of this valuable material thus received and 

 accumulated. 212 



In Darwin's hypothesis this conception of the repro- 

 ductive organs as mere glands for the reception and 

 giving up again of the germinal substance was intimately 

 associated, although in its essence quite separate and 

 independent, w r ith his further conception of the free 

 circulation of the gemmules throughout the organism; 

 and he supposes, as is known, that these gemmules were 

 produced and secreted continuously during the adult state 

 by all somatic cells indiscriminately, by those already 

 present as well as by those just appearing in consequence 

 of a new functional adaptation. Now if Galton by his 

 experiments on the transfusion of blood from a rabbit of 

 one species to the blood vessels of another belonging to a 

 related species, has provoked a thoroughly justifiabile 

 doubt of this supposed circulation of gemmules, especially 

 in so far as it was carried on in the blood vessels, the 

 original idea remained nevertheless unshaken, that is that 

 the germinal substance is assembled in the sexual glands 

 after it has been formed in some real place of origin 

 external to them. 



212 Darwin : The Variation of Animals and Plants under Domesti- 

 cation. II. P. 370, 379. 



