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VARIATION : ITS STARTING-POINT 



Since variation in the form of a plant can only be 

 observed when there has been sufficient growth to 

 evidence its existence, the question of its starting-point, 

 that is, where the first abnormal mother -cell, from 

 which the subsequent abnormal growth is derived, 

 originates, appears to be, and probably is, an insoluble 

 one. Despite this rather disheartening probability, it 

 is, however, of great interest to record the various ways 

 in which such sports have been known to declare them- 

 selves, and in this way provide at least some material 

 upon which theories, if not certainties, may be based 

 by extended investigation. In connection with Ferns, 

 and particularly British ones, which have afforded 

 such abundant material, both in the wild state and under 

 culture, by selection from the offspring of such, the finder 

 of these can throw no light upon our problem. All he can 

 say is that among possibly many thousands of the normal 

 type he has found one, or it may be several, of a distinctly 

 different one, though of the same species undoubtedly as 

 the others associated therewith. If there are more than 

 one at or near the same spot, he will probably be 

 justified in his conclusion that these are either the direct 

 offspring of some normal plant in the vicinity, which 

 had yielded such offspring through spores endowed with 

 the capacity of variation, or that equally probably, all but 

 one of them are the offspring of one plant from whose 

 spores they have sprung, as what we may term secondary 

 sports. Naturally, however, he cannot trace how that 

 first one originated. It may have, as we have said, 

 commenced as a spore on an otherwise normal plant, 

 but, on the other hand, it may have started independently 

 of the spore as an offset produced by a bulbil, but we have 



By permission of the Gardeners' Chronicle. 





