vi Preface. 



I have decided upon the latter course, because in this 

 way we are most likely to obtain a clear view of the 

 growth of Weismann's elaborate structure of theories 

 — a view which it is almost necessary, for the purposes 

 of criticism, that we should obtain. 



Having decided upon this point, it occurred to me 

 that certain advantages would be gained by removing 

 the whole criticism from the position which it was 

 originally intended to occupy as a section of my 

 forthcoming volume on the Post-Darwinian period. 

 For, in consequence of the criticism having been 

 written at successive intervals during the last six or 

 eight years as Professor Weismann's works succes- 

 sively appeared, it has now swelled to a bulk which 

 would unduly encumber the volume just mentioned. 

 Again, the growth of Professor Weismann's system 

 has of late become so rapid, that if the criticism 

 is to keep pace with it in future, the best plan 

 will doubtless be the one which it is now my 

 intention to adopt — viz., to publish the criticism in 

 a separate form, and in comparatively small editions, 

 so that further chapters may be added with as much 

 celerity as Professor Weismann may hereafter pro- 

 duce his successive works. Lastly, where so much 

 elaborate speculation and so many changes of doctrine 

 are concerned, it is inevitable that some misunder- 

 standings on the part of a critic are likely to have 

 arisen ; and therefore, should Professor Weismann 

 deem it worth his while to correct any such failings 

 on my part, the plan of publication just alluded to 



