18 Darwin-Wallace Celebration. 



and however much modified, Weismann's doctrine forms the 

 basis of modern views of heredity. 



The lucidity and beauty of his style has helped to render 

 Prof. Weisrnann the effective champion of all that is most 

 characteristic in the teaching of Darwin and Wallace, while 

 his profound knowledge of cytology enabled him to base his 

 theory of heredity on a firmer foundation of fact than had 

 been possible in the case of previous speculations. 



Prof. Weismann's works, many of them so admirably 

 translated into English, have met with universal appreciation 

 in this country. I well remember my own keen enjoyment 

 in reading his essays, such as ' The Duration of Life,' ' On 

 Life and Death,' on Continuity, and on the Theory of 

 Natural Selection. The work of this brilliant investigator 

 and writer has been of immense service to evolutionary 

 Biology ; and, apart from all matters of controversy, the 

 stimulating influence of his writings has had a wonderful 

 effect in advancing the subject. 



There is no one to whom the award of this medal could be 

 more appropriate. 



Herr DIETRICH VON BETHMANN-HOLLWEG : I thank you, 

 Sir, on behalf of Professor Haeckel and Professor Weismann 

 for the great honour your Society has conferred upon them. 



THE PRESIDENT : I should like to mention that we have a 

 communication from Professor Haeckel which I am sure 

 you would wish to hear read, and I will therefore ask 

 Professor Dendy to read it. 



ADDRESS communicated to the Afternoon Meeting 

 of the Linnean Society on the 1st July, 1908, l>y 

 Prof. ERNST HAECKEL (Jena). 



THE formal celebration of the first of July by the Linnean 

 Society, the fiftieth anniversary of the day on which the 

 joint essay by Charles Darwin and Alfred' Wallace : " On 

 the Tendency of Species to form Varieties ; and on the Per- 

 petuation of Varieties and Species by Natural Means of 



