No. 44«-] HEREDITY AND ENVIROXMEXT. 29 1 



lu which a plant hves makes a very great cHffcrcncc in th'^ 

 mechanical strength of the plant as a whole.' there is n.. dis- 

 coverable difference in the structure and other pmpcrtie^ tlu 

 protoplasm. This fact is what the foregoing di.smssi* m has lca( 

 us to expect; for upon the component panicles ol piMtoi-lasir 

 the force of gravity operates unoi-)i)osed by the l)nu\aiu \ ot air 

 or water, except such water as is in ihe'ceir-sap ;' and' as ihc 

 t'TCe of gravity is c<)ntinu()us ancl uniform in operation, thi 



ence. Does it not react accordingly ? 



Again, the force of gravity, regarded both as the attraction 

 of the earth as a whole as well as the attraction of rach 

 particle of matter for every other, has never been eliminated 

 bom any experiment. If it had been, can we imagine wliat 

 \voukl have happened? The force of gravity acts on]\ in one 



axis by means of a clinostat. so that al/ its parts will be succ es- 

 si\ely turned in this direction, and the opp,)siti..n ot centritugal 

 'M- other force to the force of^ gravity, yield interesting results m 



throw little or no light on the inriuence of gravity ujion the 

 conii)onent parts of the living structure. L'ntil .i;ra\ ity i.s elimi- 



ence is ; but rather than ignore it, we may gues^ that it> inllucnce 



influence to be. And as we know that its directive intluciuc is 

 always the same, that i)lants ot a kind under like conditions 

 •vspond in api.roximatelv like wavs. like times, and with like 

 t.-r.e to the action ot .gravity, .sending their routs dounward 



the continuous and uniform factors of the eiuiiomnent 



