S4 
PROCEEDINGS OF THE 
of the more rare and interesting plants observed during the 
two excursions to Cobham, w hich have been made by myself 
in company with other members of this Society during the 
present year. On the first of these excursions I proceeded 
from Woolwich by w r ay of Plumstead-Common, Welling, 
Bexley, Crayford, Dartford Heath, Wilmington, Sutton at 
Hone, Darent, Stone and Northfleet ; and on the second, 
when I had the pleasure of being accompanied throughout 
by our Curator, our route was by way of Plumstead Marshes, 
Wickham, Welling, Dartford, Darent, Longfield Hill, and 
Merstead to Cobham. Plaving promised this general view r of 
our course on each of these excursions, I shall now commence 
the enumeration of the several species W'hich deserve parti- 
cular notice. 
Polypogon Monspeliensis. We found this rare and beauti- 
ful grass growung abundantly on the banks of ditches, and 
in boggy places in the Marshes East of Woohvich, particu- 
larly in front (i. e.) south of the Butt or Mound in the Plum- 
stead Practice-ground. 
Polypogon littoralis. “ Near the Magazine, four miles below r 
Woohvich,” has often been referred to as one of the few places 
producing this species, and Sowerby has figured a specimen 
from that locality ; I have, however, often searched for it 
there in vain, and was therefore greatly delighted at finding 
it associated w-ith the former species in the bay, immediately 
in front of the Butt to which I have before alluded. 
On ditch banks forming the East border of the Practice- 
ground, we observed Poa distans, procumbens and maritima, 
and in the water Zannicliellia palustris, Potamogeton pectina- 
tum and Scripus lacustris with the Polygonum maritimum of 
Pay, described at our last meeting. 
At a considerable distance from this marsh, about the 
middle of the Sandy Hill leading from Woolwich to Plumstead 
Common, w r e found in the hedge-banks on the left a small 
plot of Erysimum Cheiranthoides, a plant whose foliage and 
flow r ers rival each other in elegance. 
Passing over Plumstead Common to a road called the 
King’s High-w-ay, I found in a little wood on the right of 
this road the Orobus tenuifolius of Roth. This plant which 
Wildenow, Smith, and Hooker, agree in regarding as a nar- 
row r -leaved variety of Orobus tuberosus, is considered by Don 
and others as a distinct species. The following characters 
which are permanent in cultivated plants are given by Mr. D. 
Don in the 3rd vol. of the Memoirs of the Wernerian Society, 
and sufficiently distinguish this from the common species. 
