336 ISATIS TTNCTORIA. [AuffUSt, 



Nobody can deny that there is much force in this objection, 

 though it is certain that the plant was conveyed from some place 

 and by some agency. Let the botanical geographers settle this 

 question among themselves. There are certain plants which 

 evince a partiality for railway cuttings, and (Enothera biennis, 

 Melilotus officinalis, M. vulgaris, and several CrucifercB, may be 

 cited in proof of this fact, but Isatis tinctoria has not hitherto 

 been convicted of these vagabondizing tendencies and trouble- 

 some partialities for embankments. 



But Wandsworth Common offers other examples of hard 

 nuts to be cracked by philosophical and geographical botanists. 

 Whence came Lycopodimn inundatum, Drosera rotundifolia, and 

 Osmunda regalis into their present stations at the bottom and on 

 the sides of a deep cutting opposite the New Surrey Jail? It 

 may be said, from the bog on Wimbledon Common, behind the 

 mill. Who brought them ? The gravel or ballast was taken from 

 the place where these plants now grow and carried beyond the 

 place where the plants may be assumed to have come from. 

 The soil was not taken from Wimbledon, as the lime may have 

 been taken from Guildford, and used here as mortar, but it was 

 taken from Wandsworth Common, — where none of these plants 

 were ever seen prior to the railway cutting, — and carried to the 

 valley or basin of the Wandle, beyond Wimbledon Common. 

 Were the minute seeds or spores of these non-migratory or non- 

 cosmopolitan plants conveyed to their present place of growth 

 from Wimbledon Common or from any other place by under- 

 ground tiny currents, rills, or watery percolations, or by atmo- 

 spheric currents, or by winds, storms, or by attachment to the 

 hairy or feathery integuments of beasts or birds; or were the plants 

 eaten by animals, and the undigested seeds, etc., dropped in the 

 cutting exactly where they found a suitable locality ; or reached 

 they their present abode from or through or by the agency of 

 man or by any of his modern multifarious operations, which have 

 of late very much deranged the laws which philosophic botanists 

 have made and provided for the regulation of the Vegetable 

 Kingdom ? The usual answers to these and similar interrogato- 

 ries add much more to our speculative than to our real knowledge 

 of the geographical relations of plants. 



