60 An Examination of Weismannism. 



logically intact, he refrained from concluding on this 

 account that it must be the true theory of heredity. 

 He argued, indeed, that in the main it was probably 

 the true theory ; but he guarded his presentation of 

 it by not undertaking to deny that there might 

 still be some degree of intercommunication between 

 the material basis of heredity in stirp, and the 

 somatic tissues of successive organisms. The con- 

 struction of a theory which, as a matter of theory, 

 could dispense with the Lamarckian principles in toto, 

 was seen to be a very different thing from proving, 

 as a matter of fact, that these principles are non- 

 existent — and this, even though it was seen that 

 a recognition of the principle of panmixia must be 

 taken to have considerably attenuated the degree of 

 their operation as previously estimated by Darwin in 

 the theory of pangenesis. In short, after pointing out 

 that the doctrine of stirp might very well adopt 

 the position which about a decade later was adopted 

 by the doctrine of germ -pi asm — namely, that of 

 altogether supplanting the doctrine of gemmules, — 

 Galton allowed that this could be done only as 

 a matter of formal speculation ; and that, as a matter 

 of real interpretation of the facts of nature, it seemed 

 more judicious to stop at modifying the doctrine of 

 gemmules, by provisionally retaining the hypothesis 

 of gemmules. but assigning to their agency a greatly 

 subordinate role. Or to quote his own words : — 



The conclusion to be drawn from the foregoing arguments is, 

 that we might almost reserve our belief that the structural [i. e., 

 "somatic"] cells can react on the sexual elements at all, and 

 we may be confident that at the most they do so in a very faint 

 degree ; in other words, that acquired modifications are barely, 



