Natural Habitats and Nativeness. 97 
whip, and remark ‘There was a shepherd’s shealing there once, 
that bed of nettles shows it.’ His reasoning would be true, 
_ though Mr. Reid has demonstrated this species to be interglacial 
from the D bed at Hoxne in Suffolk. It is, therefore, as old, if 
‘not much older than man in Eastern England. Here I may 
pause a moment to say the value of this geo-botanical work can 
hardly be over-estimated. Mr. Reid’s admirable and careful 
analyses, have given us a Key to many an otherwise insoluble 
problem. May he have many other successors in his special line 
of enquiry. 
To return. There was however, no doubt a time when Urtica 
dioica flourished in a definite area ‘without the least human aid ; 
that is not the question which interests us in trying to understand 
its peculiar position to-day. It is now in a state of semi-depen- 
dence. Who can to-day define the hmits of its present position ? 
It has nothing to do with cultivation properly so called, but 
father with an increasing soil fertility—with nitrogen and potash. 
Would not, such species be best entitled “ Followers (1) of man ?” 
aced it inits own category. It is found in the richest pastures 
have ; and its presence causes a marked change in their flora, 
ss the scythe comes too frequently to permit them to develop. 
sy destroying the pasture grass, with its clustering annual stems, 
Oa certain extent it acts like a tilth crop, and a whole tribe of 
lowers (2) of cultivation, and Frequenters (1) of broken ground, 
as Stellaria media, Bursa, Veronica agrestis, Lamium album 
L. purpureum, &c., according to soil and situation, find a 
othold along with it. They obtain soil room amid its stems, 
md are protected by its well armed leaves from the ravages of 
stock. All these species can live on in pasture which is so sandy 
poor that competition is not keen, but none of them can 
nd 
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