EXPERIMENTS IN PLANT HYBRIDISATION. 



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made Abbot, and died January 6, 1884. The experiments described in 

 his papers icere carried out in the garden of his Convent. 



Besides the tiuo papers on hybridisation, dealing respectively with 

 Pisum and Hieracium, Mendel contributed to the Briinn journal observa- 

 tio7is of a meteorological character, but, so far as I am aware, no others 

 relating to natural history. — W. Bateson.] 



Introductory Remarks. 



Artificial fertilisation, such as is effected with decorative plants in 

 order to obtain new variations in colour, has led up to the experiments 

 which will here be discussed. The striking regularity with which the 

 same hybrid forms always reappeared whenever fertilisation took place 

 between the same species induced further experiments to be undertaken, 

 the object of which was to follow up the developments of the hybrids in 

 their progeny. 



To this object numerous careful observers, such as Kolreuter, Gartner, 

 Herbert, Lecoq, Wichura and others, have devoted a part of their lives 

 with inexhaustible perseverance. Gartner especially, in his work " Die 

 Bastarderzeugung im Pfianzenreiche " (The Production of Hybrids in the 

 Vegetable Kingdom), has recorded very valuable observations ; and quite 

 recently Wichura published the results of some profound investigations 

 into the hybrids of the Willow. That, so far, no generally applicable law 

 governing the formation and development of hybrids has been successfully 

 formulated can hardly be wondered at by anyone who is acquainted 

 with the extent of the task, and can appreciate the difficulties with 

 which experiments of this class have to contend. A final decision 

 can only be arrived at when we shall have before us the results of 

 detailed experiments made on plants belonging to the most diverse orders. 



Those who survey the work done in this department will arrive at 

 the conviction that among all the numerous experiments made, not one 

 has been carried out to such an extent and in such a wa^y as to permit of 

 the possibility of determining the number of different forms under which 

 the offspring of hybrids appear, or so that these forms may be arranged 

 with certainty according to their separate generations, or that their 

 mutual numerical relations can be definitely ascertained. 



It requires indeed some courage to undertake a labour of such far- 

 reaching extent ; it appears, however, to be the only right way by which 

 we can finally reach the solution of a question the importance of which 

 cannot be overestimated in connection with the history of the evolution 

 of organic forms. 



The paper now presented records the results of such a detailed 

 experiment. This experiment was appropriately confined to a small 

 plant group, and is now, after eight years' pursuit, concluded in all 

 essentials. W^hether the plan upon which the separate experiments were 

 conducted and carried out was the best suited to attain the desired end 

 is left to the friendly decision of the reader. 



Selection of the Trial Pl.\^-ts. 

 The value and utility of any experiment are determined by the 

 fitness of the material to the purpose for which it is used, and thus in 



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