66 



vast majority of such "sports " it is entirely impossible to 

 attribute them either to (i) change of environment, (2) 

 difference of environment, (3) any response to environ- 

 mental influences, or with a few exceptions to hybridiza- 

 tion. For some years past the writer has endeavoured by 

 replies to papers insisting on the importance of these three 

 conditions, to lead to a study of the literature we have 

 alluded to, and even of the plants themselves, but all in 

 vain; after a time the same insistence crops up again, 

 literally repeated, and without the faintest reference to the 

 evidence ottered and which would inevitably confute the 

 theory involved. 



Although the reasons upon which the writer's belief is 

 founded have been frequently stated by him, a brief 

 reference to the ordinary conditions under which Fern 

 sports are found may not be out of place. It may be 

 asserted, as a general rule, that they are discovered so 

 closely associated with the normal or common forms (1) 

 that they have frequently to be disentangled from such, 

 both as regards their fronds and their roots, so that the 

 environment is consequently identical; (2) that they are 

 often found on hillsides, in glens and in other situations 

 which quite preclude the possibility of any local change of 

 environment for a long period; (3) that ''sports'' occur 

 to a predominant extent in species of which only one of 

 the genus occurs here, such as Athyrium, Scolopendrium, 

 Blechnum, which excludes the idea of hybrid origin dear 

 to some theorists; and, finally, (4) the forms assumed 

 afford no appreciable evidence of sympathetic response to 

 environmental conditions. They will, of course, be stunted 

 in dry and uncongenial exposed habitats, but when 

 removed to sheltered conditions they are quite as likely to 

 grow robustly as to retain a stunted or congested character 

 such as a sympathetic response would involve. 



That the writer is not prepared to otter a counter theory 



