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JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



PLANT VARIATION UNDER WILD CONDITIONS. 

 By Charles T. Druery, V.M.H., F.L.S. 



With special reference to Professor Henslow's very interesting paper, 

 pages 71-83 of the present volume, my experience in connection with 

 the phenomena of variation in the British species of Ferns, which 1 

 have studied now for some twenty-five years, leads me to the conclusion 

 that he, like many other botanists, is unaware of the great variability 

 evinced under normal conditions of growth. Hence I venture to think 

 that the following facts, cited on the opposite side of the case, may 

 appropriately be set forth for the information of the Fellows of the 

 Society. Owing to certain peculiar circumstances, there is, I believe, no 

 family of plants other than Ferns which for at least half a century has 

 been subjected to such careful search in wild habitats for those "sports" 

 which form a class of varietal forms distinct from the smaller and merely 

 individual differences which characterise most plants originating through 

 seeds or spores. The results of such research have, moreover, during the 

 whole period been carefully recorded with descriptions, localities, dates, 

 and finders' names. Furthermore, the plants themselves, being perennial 

 and of quite indefinite longevity, have mostly been preserved in a living 

 condition, and exist to the present day in the numerous collections about 

 the country. We have therefore not only a reliable record, but also a 

 unique mass of living material, in addition to those herbarium specimens 

 in our museums and elsewhere, which as a rule form the mainstay of the 

 student, but are in many ways greatly inferior to the living examples, as 

 subjects for reference. This being so, it is easy to verify the data upon 

 which I base my theory as opposed to Professor Henslow's, which is : 



1. That plants vary fully as much under purely natural, i.e. normal, 

 conditions, as they do under culture. 



2. That the " sports " discovered are not due in any way to change 

 of environment or response to altered conditions. 



3. That their diverse nature indicates a confirmation of Darwin's 

 theory of indefinite variation in all directions, instead of Professor 

 Henslow's that the variation is sympathetic with or responsive to the 

 environment. 



Before considering these three points, of which 2 and 3 are really 

 varied forma of the same idea, I may point out that the prevalent notion 

 that plants vary more under culture than under wild conditions is largely 

 due to the fact that all plants under culture are placed under the most 

 favourable conditions for the discovery of variation, while those under 

 natural conditions are in precisely the opposite position. Plants under 

 culture are as a rule under observation from their germination upwards, 

 and they are grown in large numbers of the same species or variety 

 together, so that any deviation is easily noticed. 



Wild plants, on the other hand, grow as a rule intermingled with 

 numerous other genera and species, and are moreover widely scattered 



