PANGENESIS IMPLIED. 137 



The " use " or " work " or " function " of muscles, 

 nerves, bones, teeth, skin, tendon, glands, ducts, 

 eyes, blood corpuscles, cilia, and the other con- 

 stituents of the organism, is as widely different as 

 the various parts are from each other, and the 

 effects of their use or disuse are equally varied 

 and complicated. 



USE-INHERITANCE IMPLIES PANGENESIS. 



How could the transmission of these varied 

 effects to offspring be accounted for ? Is it pos- 

 sible to believe, with Mr. Spencer, that the effects 

 of use and disuse on the parts of the personal 

 structure are simultaneously registered in cor- 

 responding impressions on the seminal germs ? 

 Must we not feel, with Darwin apparently, 1 that 

 the only intelligible explanation of use-inheritance 



1 Variation of Animals and Plants under Domestication, ii. 388, 

 398, 367 ; Life and Letters, iii. 44. 



