278 MR. W. A. NICHOLSON ON BOTANY OF SUTTON. 
any, there was a retardation of flowering, owing to the cold 
winds, or other meteorological influences. 
The winter aspect of the region is a startling contrast to 
the summer one, though possessing much interest, even 
from an aesthetic point of view. On 10th Dec., 1905, several 
flowers of Ranunculus Flammula, L. were found, though the 
dykes had a thin coating of ice on their surfaces, through 
which the bright green submerged leaves of Hottonia palustris, 
L. could be seen. Stratiotes, of course, had sunk to the 
bottom, but many plants looked green and healthy, and 
Sparganium minimum, Fr. appeared almost as fresh as in 
the summer. 
Let us turn now to the Flora of the marshes proper. 
Though there is a continual formation of a coarse kind of 
peat going on in our marshes, it is very unlike the peat which 
is characteristic of the moors of Yorkshire and Derbyshire, 
which is mainly composed of Sphagnum. 
From Sendtner’s experiments, quoted by Schimper, it 
appears that calcium acts as a poison on Sphagnum.* It does 
not seem clear from the context, whether by calcium is 
meant calcium carbonate, or the metal calcium, as free 
calcium is not known to occur in nature. If the calcium 
carbonate acts as a poison on Sphagnum, it is strange that such 
large patches of this Moss should occur at Sutton, impregnated 
as the soil and waters are with this salt. 
An estimate of the rate of growth of the peat in Norfolk 
was made by the late John Gunn in his ‘Geology of Norfolk.’ 
I cannot do better than quote his words. “ The formation 
of turbaries is very interesting and important for the deter- 
mination of the age of the remains embedded in them and 
the remains frequently reflect light upon the age of the 
turbary. The discovery of several coins in Catfield, the latest 
of which was of the reign of Edward VI., proves that there 
was water when the coins were sunk, and the peat has grown 
up since, and become a solid turf-ground. It is formed by 
the annual growth and decay of several marsh plants, as 
Typha latifolia and T. angustijolia, Scirpus lacustris, Cladium 
* ‘ Plant Geography,’ p. 95. 
