THE GERM-PLASM THEORY 87 



Again we hear of " internal forces " ; of " vital 

 affinities " (vol. i. 347) ; and of mysterious 

 " stimuli." 



" That double determinants, male and female 

 for the differently formed parts of the two sexes, 

 must be assumed to exist in the germ-plasm has 

 already been said, and we have to suppose that 

 the same stimulus usually unknown to us 

 which incites the determinants of the primary 

 sexual characters to activity also liberates those of 

 the secondary characters." Vol. i. 389. 



Some of these may be external stimuli, but there 

 are also " intra-organismal stimuli, that is, the 

 influences exerted in a mysterious manner by 

 other parts of the animal on parts which are in 

 process of regeneration " (vol. ii. 24). Finally we 

 read of " constellations of energy, co-ordinations 

 of matter and the energies immanent therein " 

 (vol. i. 403). 



But it is clear that none of these things are, in 

 their describer's mind, at all like a " vital force," 

 for this he denies and brings arguments to show 

 that it is not necessary " to fall back upon a belief 

 in a spiritus rector in the organism " (ii. 19). 



Lastly, has the author anything to tell us as to 

 how these vital units first came into existence ? 

 Yes, he has essayed a reply to this question also. 



As we have already concluded that " at no time 

 have organisms been called forth out of nothing 

 by the mighty word of a Creator " (i. 6) though 

 nothing is said as to the possibility of a Creator 

 having formed living organisms from pre-existent 



