CHAPTER IX. 



HYBRIDS. 



Camerarious, in 1694, thoug:ht, on certain grounds, that 

 hybrids could occur, and Ginelin found a new Delphinium 

 in his garden which he concluded was a hybrid. Linnaeus 

 appears to have been successful in the production of a hybrid 

 between Tragopogon pratensis and T. porri/oUus; this flowered 

 in 1769, though as early as 1719 Thomas Fairchild produced 

 a hybrid of Dianthus Caryophyllus and Z>. barbatus. 



As early as 1791 Koelreuter produced a large number of 

 hybrids. These early experiments in hybridization gave un- 

 doubted proof to those who doubted it, of the sexuality of 

 plants. Koelreuter produced his first hybrid between Nicot- 

 iana rustica and N. paniculata. Thomas Andrew Knight, 

 during the latter part of the Eighteenth Century, did a great 

 deal of work in hybridization. 



Of the later workers, from 1826 to 1880, mention should 

 be made of Oaertner, Herbert, Naudin, Gadron, Focke and 

 a host of modern workers. 



The term cross is used to designate the oflFspring from 

 the union of two diflerent plants of the same species or 

 variety, the union of the variety being more violent than that 

 of the same species. The hybrid is the result of the union 

 between two species, as blackberry and raspberry. It is 

 difficult in some cases to say what constitutes a species, as 

 botanists do not always agree as to its limits. In some few 

 cases hybrids have been produced between two distinct 



