X] PANGENESIS. 223 



CHAPTER X 



PANGENESIS. 



A rrovlslonnl Hypothesis Bupploinpntinp " Nntiira! Solocflon."— St/itemcnt of the Hy- 

 pothesis.— Diflicnlty ns to MtiltUudo of Gonimulos.— As to Ccrtiiin Mo<lc8 of Uc- 

 produotion. — As to Formntions without tlio I'oqiiislto Gpmmiiles. — Mr. I>ewos nnd 

 Prof. Dolpino. — Difllculty n.s to l)c vclopmcnt.il Force of ricmmnlcs.— As to their 

 Pponfnneous Ussion.— Pniipenesls nnd Vitalism.— Pnmdo.xicnJ Reality.— rnnpcne- 

 flis Pcnrcoly fliipcrior to Anterior Hypothesis. — Huflbn.—0>Ten.— Herbert Spen- 

 cer. — " Ociiuniilea " oa MyBtcrlous tia " Phyaiologlcal Units."— ConcJusion. 



In addition to the theory of " Natural Selection," by 

 which it has been attempted to account lor the origin of 

 species, Mr. Darwin has also put forward what he modestly 

 terms " a provisional hypothesis" (that of Vangcncsis)^hY 

 which to account for the origin of each and every individ- 

 ual form. 



Now, though the hypothesis of Pangenesis is no neces- 

 sary part of " Natural Selection," still any treatise on spe- 

 cific origination would be incomplete if it did not take 

 into consideration this last speculation of Mr. Darwin. The 

 liypothesis in question may be stated as follows : That each 

 living organism is ultimately made up of an almost infinite 

 number of minute particles, or organic atoms, termed" gem- 

 mulos," each of which has the power of n^producing i(s 

 kind. Moreover, that these particles circulate freely about 

 the organism which is made up of them, and are derived 

 from all the parts of all the organs of the less remote an- 

 cestors of each such organism during all the states and 

 stages of such several ancestors' existence ; and therefore of 

 the several states of each of such ancestors' organs. That 

 such a com])lete collection of gemmulcs is aggregated in 



