148 EXOTIC PLANTS ABOUT LONDON IN 1865. 
there appeared last summer a large number of foreign plants, many of 
which I collected in two visits I paid the locality with my friend Mr. 
Naylor, of Edinburgh, who detected the station, and who went several 
times to the spot, and always succeeded in finding something new. 
The origin of these plants is the same ultimately as that of the exo- 
tics found at Wandsworth—the sweepings of corn used and stored up 
at Messrs. Watney’s brewery at Thames’ side. This refuse is sold to 
farmers in the neighbourhood as manure for grass lands, but its 
small fertilizing value must certainly be overbalanced by the evident 
risk of introducing foreign weeds into the cornfields round. This, how- 
ever, has. not been considered by the Surrey farmers, who pile the 
“ manure" in heaps on the borders of the fields till wanted; and it is 
on and around these heaps that the exotics sprang up last year in great 
abundance. Their origin is evident, and is now clearly stated in order 
that no mistakes may be made in future by botanists who may find 
these certainly alien plants, which have no claim whatever as yet to a 
place in our Flora. Should any become naturalized permanently in 
the district, it is still more important that the history of their introduc- 
tion should be known. 
Appendix B. of Brewer’s ‘ Flora of Surrey’ is a list of the exotics 
collected by Messrs. Irvine, Woods, Britten, and others, on the ground 
at Wandsworth where the refuse of the distillery was thrown out and 
corn sifted. A few more species are recorded in the new series of the 
‘Phytologist,’ and in Mr. Irvine's * Handbook of British Plants.’ 
These plants were noticed in 1851, and, though at first numerous, 
few retained their ground many seasons. In 1863, I saw only about 
twenty species 
The origin of the Miteham and Wandsworth plants being identical, 
the species are, as might be expected, in the main the same. Nearly 
half, however, of those enumerated in the following list have not been 
recorded from Wandsworth. It is probable that the more favourable 
conditions of soil and situation eaused many seeds to germinate at 
Miteham whieh would have perished in the exposed ground at Wands- 
worth'; and it is certain that all the plants attained a greater degree of 
luxuriance and perfection of growth in the former than the latter place. 
I have little doubt, however, that the high temperature of last season 
enabled several pes io come to maturity which in ordinary years 
s would have died. 
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