HORTICULTURAL SOCIETY OF NEW YORK. 



with species the more violent the cross that can be secured the more variable 

 will be the hybrids in the second generation, and the more likelihood there is 

 of securing distinct forms or monstrosities. Second, that when working with 

 plants which are themselves of crossbred or hybrid origin, the peculiar 

 attributes of the particular plants used for breeding purposes cannot be counted 

 upon to appear in the mongrel offspring except, in so far as these characters 

 form important dominant or recessive characters in the breeding of the parent 

 plants. 



The marvelous results achieved by some of our modern plant breeders seems 

 to lie in their wonderful skill as manipulators of plants. Crosses have been 

 successfully made by these men and fertile seeds obtained from plants which 

 have been considered incompatible and so entirely distinct that it was considered 

 heresy to seriously consider the question of making such a cross. I am free to 

 confess that with ninety-nme persons out ot every hundred engagmg m such work 

 I believe the results would be "nil." The success of the one proves his superior 

 skill and ability to discern the conditions essential for success. The factors then 

 which may be considered as contributing to the sporting of plants are ; Extreme 

 conditions in the environment, such as marked changes in latitude, altitude, soil 

 conditions, as from alluvial to desert ; Increased food supply, the results of an 

 excessive use of plant foods or of cultivation ; and Violent or continuous 

 cross-breeding. 



THE ORIGIN OF SPECIES BY SPORTS AND 

 MUTATIONS 



BY D. T. MACDOUGAL, JANUARY II, I905. 



It was in 1590 that, in a garden at Heidelberg, a sport of the celandine occur- 

 red which had cut leaves and otherwise differed from the ordinary plant. This 

 plant had never been known to appear again except as a seedling from the 

 original one. It was something quite distinct and quite permanent, coming 

 true from seed. That was the first record of the mutation of species. Darwin 

 had his attention attracted to the interesting phenomena of the sporting of plants, 

 and wondered whether in some way that was not connected with the produc- 

 tion of new species. He was put off the track of this idea by the persuasions 

 of his friends, especially by Wallace; and further investigation was abandoned 

 along these lines. It was about 1865 that Mendel made public the results of 

 his work on the peas. Then followed the pangenesis theory of Darwin that 

 each organ on the plant as it would finally develop was represented in the 

 seed by a special cell, or rather a gemmule — each leaf, each twig, each separate 

 part was the product of a certain special division of the seed. The speaker 

 paid a high tribute to the methods and to the honest investigations of Darwin. 

 So great was the interest of Darwin and his work that, from that time, until 

 recently, people ceased to study the problems of organic evolution and discussed 

 Darwinism itself. They wrote books about Darwin and later other books on 

 the books about Darwin. It was in 1880 to 1890 that De Vries became interested 

 in the problems that were before the world. He reasoned that the principle 



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