34 
short space of time the entire surface became covered thickly with 
young grass. The species were never identified, as the material 
was removed before the flowering spikes became visible. A yet 
more remarkable instance is recorded in the Linnean Society’s 
Transactions, some three or four years ago, when a short paper 
was read before the members to the following purport. Shortly 
before the date of the paper referred to, the River Avon Navigation 
Commissioners effected considerable improvement in the channel 
towards Bristol, by dredging the bed of the river. An old quarry- 
hole of considerable extent adjoined the river, and into this handy 
receptacle the mud was tipped until the excavation was made level 
with the surrounding surface. No sooner was it sufficiently indu- 
rated by the escape or evaporation of the water, than the top was 
overspread with vegetation of a miscellaneons character, mostly, 
however, of exotic origin, and bearing a striking resemblance to 
that found about Silloth. The port of Bristol is some centuries 
older than Silloth, and it is impossible to imagine how long some 
of the mud thus brought to the surface may have remained 
undisturbed at the bottom. The similarity in species of the 
plants collected at these two widely separated stations leads to the 
inference that grain importation is probably the common origin of 
both. The matter is worthy of further thought and investigation. 
