86 MASSACHUSETTS HORTICULTURAL SOCIETY. 



MEETING FOR LECTURE AND DISCUSSION. 



Saturday, February 23, 1895. 

 A Meeting for Lecture and Discussion was holden today at 

 eleven o'clock, the President, Nathaniel T. Kidder, in the chair. 

 The following paper was read by the author : 



Experimental Evolution Amongst Plants. 



By Professor L. H. Bailey, Cornell University, Ithaca, N. Y. 



[Before entering upon the proper subject of the hour, the 

 speaker made some introductory remarks concerning the present 

 state of belief in the theory of evolution. A brief abstract of 

 these remarks is here given.] 



Every thoughtful person at the present day is an evolutionist, 

 although he may not know it. Everyone now considers every 

 movement, either of human society or of natural forces, in 

 connection with its origin and gradual growth or development. A 

 person may be an evolutionist without subscribing to any 

 particular doctrine of the origin of species or to any particular 

 dogma either of religion or science. Evolution in the abstract 

 means merely a gradual unfolding or growth. In the organic 

 world, the term is used to designate the belief in the origin of 

 one form or one species from another. Its use does not necessarily 

 imply that one believes in the origin of all things from one 

 species or from many. It simply means that a person sees 

 growth, development, and progression in nature. 



There are two chief reasons for the belief in the evolution of 

 animals and plants : first, the fact of struggle for existence ; second, 

 the fact that there are constantly recurring physical changes. The 

 struggle for existence is the necessary result of the multiplication 

 of species, and the physical changes necessitate a constant 

 modification of the species in order that they may fit themselves 

 into the environment. 



There are five chief lines of proof of evolution : first, the 

 record of the rocks, or paheontology ; second, the fact that animals 

 and plants are widely variable, — so much so that no two individuals 

 in the world are exactly alike ; third, we can see adaptive changes 

 taking place, particularly among plants which are widely dissemi- 

 nated by man or which are brought under domestication ; fourth, 



