Annual Report of the Council. xli 



writings on many detailed and highly technical subjects. His 

 earlier papers on the development of the house-fly and on the 

 natural history of the Daphnids and Ostracods, although of very 

 high quality and interest, were overshadowed in importance by 

 the publication in 1883 of his great work on the " Origin of the 

 Sexual Cells in the Hydromedusae." It was in this thesis that 

 his conception of the immortal germ plasm that passes on from 

 generation to generation, immune from the need for that periodic 

 death the body-plasm requires, was first adumbrated ; and from 

 this conception arose the long series of philosophical specu- 

 lations which has given rise to the expression "Weismannismus." 



As a young student of the morphology of the Coelenterata 

 at the time of the publication of " Die Enstehung," the writer 

 can well remember the powerful influence this paper had, not 

 only on our ideas of the living body of animals in general, but 

 also on our conceptions of the relation between the " medusom" 

 and "hydrosom" stages of the Hydromedusae. The careful 

 and skilled microscopical study, the orderly sequence of the 

 points and the final conclusive arguments that seemed to settle 

 the matter under discussion once and for all time raised this 

 great work to the level of a classic, which we read with interest 

 and enthusiasm. The essays on the " Duration of Life " and on 

 " Life and Death," which appeared about the same time, soon 

 became the subjects of eager discussion in the junior scientific 

 societies of the early eighties, and opened up new fields for 

 original work and speculation among the young zoologists. 



At the beginning of the Long Vacation of 1884 the writer, 

 attracted by the fame of Weismann, paid a visit to Freiburg and 

 spent a few weeks there working in the zoological laboratoiy. 

 He can remember well the charm of Weismann's personality, 

 his interest in the work of the German and of the many foreign 

 students who were engaged in researches under his directions 

 and the stimulus of his lectures and conversation. 



Weismann came to Manchester in 1887 to attend the meet- 

 ing of the British Association, and was the guest of his former 

 pupil, Dr. G. H. Fowler, in York Place, at the time a Berkeley 



