HYBRIDIZING AND CROSSING. 73 



True hybrids are generally forced productions, but cross 

 fertilizing is constantly going on naturally among nearly 

 all cultivated plants. . 



During the last few years many new varieties of grapes 

 have been brought to notice that are claimed to be true 

 hybrids, and doubtless many of them are ; but it is to be 

 regretted for the cause of science that nearly all of these 

 are in part a mixture of the varieties of Vitis Labrusca, 

 or its direct offspring ; for of all the known native 

 species this is the most variable, producing of itself, with- 

 out being fertilized by other species or varieties, almost 

 every conceivable shape, color, and quality of fruit, as well 

 as a great variety in leaf, stem, and growth. 



I think that I may safely assert that until some other 

 varieties and species have been operated upon than those 

 heretofore employed, but little reliance can be placed upon 

 the assertions that are constantly being made about this 

 or that grape being a true hybrid. 



We know that plants in a state of nature generally per- 

 petuate their species and varieties with great uniformity. 

 Yet a slight change is sometimes observed, and it has been 

 upon these variations that pomologists and florists have 

 mainly depended as the starting-point from which they 

 produce their innumerable varieties. 



The effect produced by change of soil and climate upon 

 plants when removed from their native habitats has long 

 been observed, and their variations turned to valuable 

 account. Although these changes have been slow, yet by 

 the preservation of them we are indebted to most of the 

 valuable fruits and flowers now in cultivation. 



When plants are removed from one country to another, 

 and become acclimated, the effects of this change will 

 sometimes show itself in the seedlings grown from them 

 in a distinct and wonderful manner, so much so that some 

 are inclined to think that it is the result of accidental 

 hybridization. These phenomena lead many to believe 



4 



