Lees : The Volieface of Flora — A Rejoinder. 



2 33 



answerable. I recollect the time when it was practically unknown 

 in the suburbs of Leeds, now it is occasional in them, in 

 neglected corners of shrubberies, among- Raspberry canes, and 

 Rhubarb beds. It spreads by its light feathered seeds ; a 

 solitary one season, left to seed and the next year it will be 

 detectable, on bare spots between a crop, by the dozen within 

 a few hundred yards ! 



When I wrote that the natural stay of species in an area 

 may be 'long or short,' I certainly did not intend the latter 

 adjective to convey any period much under 25 years. A year or 

 two back (I have not access to the numbers) in the 'Journal of 

 Botany ' I adduced such ' positive evidence ' as Mr. Moss in 

 concluding his article calls for. I repeat one case, ever fresh in 

 my mind. In 1876-8 Linwood warren, in mid Lincoln (near 

 Rasen, where I then resided) was a wet peaty tract, water- 

 logged sand on Kimmeridge clay, and it produced several rare 

 Sedges, Lycopodiiun inundatuni, Breutelia arcnata, etc. I left 

 the district. Examined again in the late Eighties, some water- 

 cuts had been made and many seedling firs had encroached on 

 the moor, and were growing with Serratula and Vicia Cracca 

 where none of the trio grew, or could have grow r n, before. 

 Again, at my last visit in 1896 or 1897, the ground was for the 

 most part well-bushed, heather and ling clad, and produced 

 hundreds of fine plants in full flower of Gentiana Pnenmonanthe. 

 I daresay some draining had been effected by Colonel Conway 

 Gordon, and some spruces planted for cover, but the old bog 

 had vanished, grown drier from blown sand off the adjacent 

 Hamilton hill, the flora had changed completely, and not 

 wholly or in larger part by consequence of unnatural inter- 

 ference. I repeat, in a greater or less degree, slowly or rapidly, 

 this sort of change may be observed all over our country ; least 

 conspicuously, of course, on elevated, remote moorlands, and 

 far-from-railway woods. 



It is not a fair test of the truth of this general Proposition, 

 to pick out a few cases of species that have persisted (though 

 admittedly diminishing) over long years within the ring-line of 

 one peculiarly extensive parish, and claim they quash a definition 

 of what in some degree comes under every botanist's notice. 

 In such a parish there is little room for change of actual site in 

 the species that prevail. On the moors alone is the hand of 

 man idle, the ground there is already occupied by millions 

 ot well-rooted Callunas and Vacciniums, w hose acres of grow th 

 are not rudely-enough riven and displaced by lightning, rain 



1900 August 1. 



