24 MASSACHUSETTS HORTICULTURAL SOCIETY. 



the molecular movements and mutations of which they are the 

 expression. 



Blossoms of fruit plants that are habitually self-fertilized some- 

 times indicate degeneration, as shown in the reduction in the size 

 and number of the stamens and quantity of the pollen, the latter 

 being sensitive to barren soil and inclement weather. A too 

 energetic vegetative system will likewise surely affect the repro- 

 ductive. 



No new organic form can be directly produced, but organisms 

 may be created under new conditions of life which are such as 

 to influence and transform them. All of our fruits, originally 

 descended from wild species, have been transformed b}' the 

 peculiar conditions of culture. In their native habitat the same 

 forms are produced year after year ; but in the garden great 

 changes are made by the gardener, who, skilled in the art of 

 selection, is enabled arbitrarily to create entirely new conforma- 

 tions by propagating according to a plan under the influence of 

 special conditions. He emploj's only the privileged beings for 

 propagation, while natural selection without a plan acts more 

 slowly to produce a particular kind of individuals. New species 

 arising from natui'al selection will maintain themselves more 

 permanentl}' and will return less easily to the original form than 

 the products of artificial selection, and will maintain themselves a 

 longer time, although the nature of the transformation and the 

 means by which it is produced are the same in both. Every 

 species of domesticated fruit transmits to its descendants the 

 peculiar individual qualities acquired during its existence as well 

 as those which it inherited ; and if the}' should become wild, 

 would experience changes that seem to be adaptations to their 

 new mode of life, and relapses into the ancient form out of which 

 the cultivated had been developed. The longer a desired pecul- 

 iarity of a new kind of fruit has been transmitted by inheritance, 

 the more certainly will it be retained. Fruit plants in their 

 wild state are subject to variation, and under the influences of 

 their environments do assume certain new peculiarities in vital 

 activity, composition, and form, which have not been inherited. 

 Permanent variations are often produced bj* causes which develop 

 diseases that are only dangerous adaptations of the organism to 

 injurious conditions of life. Fruit plants in a cultivated state 

 are quite liable to become sterile ; there is no development of the 



