62 ANNALS NEW YORK ACADEMY OF SCIENCES 



oration festivities celebrating the two hundredth anniversary of the birth 

 of Carl von Linne. The whole scientific vi^orld unites in grateful veneration 

 of an admirable scholar, whose reputation is least of all lost in the land 

 where he spent three of the most fruitful years of his life. Our Senate ex- 

 presses its feelings of cordial sympathy with the way in which the New York 

 Academy of Sciences intends to celebrate the anniversary of his birth by 

 the erection of an architectural monument symbolizing the work of a man 

 whose genius embraced the two realms of living nature. 



For the Senate 



W. NoLEN, Rector Magniflcus. 



H. P. WiJSMAN, Secretary. 



Professor A. A. W. Hubrecbt, University of Utrecht. 



{Honorary Member of the Academy.) 



The great Swede whose birth — now two hundred years ago — will be 

 commemorated all over the world on Ma}' 23, passed many years of his life 

 in Holland. It is thus natural that inany local reminiscences are connected 

 with his name in different parts of this country. If we allow our thoughts 

 to go back for more than a century and a half, we can imagine Linnaeus 

 roaming about on his botanical excursions over those same fields between 

 's Graveland and Hilversum where Hugo de Vrics lately encountered an 

 emigrant from the United States (Oenothera lamarckiana) that was to be- 

 come a starting-point for new and important speculations about the species 

 problem. 



The foundations for an answer to that problem were laid in a quite mas- 

 terly manner by Linnaeus. In the latter half of the nineteenth century we 

 have, however, been accustomed, after reading Darwin's works, to consider 

 the problem as non-existing; species, apparently, being in slow and imper- 

 ceptible continuity. 



Hugo de Vries has again limited species between the occurrence of two 

 mutations, each species thus being a real entity in time and in space. This 

 does not prevent de Vries from being at the same time one of the stanchest 

 disciples of Darwin, in whose steps he is treading. 



Linnseus's species differ from de Vries's in that they are the primary 

 network between the meshes of which de Vries has spun out the lacework 

 of the mutation theory. 



The new generations thus attempt to continue Linnreus's and Darwin's 

 work, and unite in paying homage to the memory of the foimder of the 

 " Systema Naturae." 



