MR. W. A. NICHOLSON ON BOTANY OF SUTTON. 273 
Under the best circumstances, it is well to have the roof 
cleaned down every five years or so, as the growth of moss is 
injurious, and the reeds are liable to get a little loose. The 
best material for the ridge of the roof is sedge, but it is not 
much used now. as it is less easily procurable than straw, 
and the hands of the workers are likely to be cut by the sharp 
edges of the stems. 
The growth of the Reed-beds at Sutton is not so good as it 
was. The reason may be, that as the beds rise by their own 
growth they get less water, and in consequence, there is an 
invasion of the Reed-mace. A little salt from the tides is 
supposed to be beneficial to the growth of the Reed. Dr. 
Marshall Ward states Phragmites as an indicator of a 
sufficiency of potassium salts, in moister soils. 
The use of reed-thatched roofs seems to be on the increase 
for ornamental buildings. 
I am not aware if Cladium is utilised specially in the Sutton 
district, but it was formerly “ considered as a valuable natural 
crop ” in the Fenland, and was used for “ lighting fires at 
Cambridge and other places.” Bab. Flora Cam., p. 253. 
Large quantities of the stems of the Bulrush (Scirpus 
lacustris, L.) are cut yearly, and are used in the manufacture 
of horse-collars, baskets, and matting. The matting is made 
of stems plaited in strips about 4 inches in width. The 
strips are eventually sewn together to form the required size. 
I was informed at the rush-factory in Norwich, that there is 
a considerable demand for this matting for laying under 
carpets, to protect the latter from contact with the bare 
floor. The baskets made here are very neat and serviceable, 
but the horse-collars form the principal part of the industry. 
In the days of rush-lights, the trade in Bulrushes was carried 
on in Norwich at a rush-fair, which many of the older inhabi- 
tants can remember. 
The third, or Naias type consists of “ Plants rooted in the 
soil, or free-swimming with long flowing shoots.” The free- 
swimming forms include 
Utricularia vulgaris, L. 
U. MINOR, L. 
U. intermedia, Hayne. 
