THE FAUNA AND FLORA OF FLORDON COMMON. I77 
noted among the hedgeside vegetation. Helix caperata in the 
pit, Arion ater (Linne) with one specimen subrufous on the 
marsh, and Pisidium pulchellnm (Jenyn) in a pond at the 
west end of the common. Vertigo angustior had only 
been found once previously in Norfolk, and that was by 
Mr. Mayfield on Roydon Fen. Limncea stagnalis and 
Limncea pereger are very abundant in the pools on the 
marsh. 
For the purpose of obtaining a general idea of the flora of 
the common, for two years we visited it from early spring 
to late autumn, identifying the various plants, noting their 
habitat, and, so far as was possible, their distribution. The 
plant associations of the common may reasonably be divided 
into three : (1) that of the water, (2) that of the marsh, and 
(3) that of the long narrow strip of ground a few feet above 
the marsh-level, and of the parish pit. 
Plants of the Water. 
The water area includes the stream which runs on the 
south side of the common. On the eastern portion there is 
very little vegetation either in the stream or at the sides, 
the water running swiftly in short reaches on a gravelly 
bottom, with Zannichellia palustris in a few places. At 
each turn the water gradually undermines one bank and 
silts up the opposite side, so that although perpetually 
changing its course it never gets wider. The more westerly 
portion of the western common is likewise bounded by the 
brook which tinkles as it flows over its stony bed in a manner 
reminiscent of the Yorkshire dales rather than of Norfolk. 
Overhanging the water almost at the western boundary is 
a willow on which grow specimens of Polypodium vulgare, 
Ribes grossularia, and Rubus rusticanus. Part of the northern 
boundary of the eastern common is a ditch containing a con- 
siderable amount of water early in the year, but partly dry 
in September. Hottonia palustris is here plentiful. On the 
marsh of this part of the common there are also ditches and 
scores of pools, mostly of small size, and containing Chara, 
N 2 
