62 THE ESSEX NATURALIST
Mosses at Black Notley Churchyard
BY A. J. PETTIFER
The thousanth meeting of the Club provided me with two mosses for the
herbarium on account of their associations.
The first, growing on John Bay's tomb, was one of our commonest mosses,
the Screw Moss, Tortula muralis Hedw., growing in hoary bluish-green tufts.
Its leaf is oblong with a blunt point, the nerve yellowish and excurrent in a
long hyaline hair. Capsules are freely produced and the 32 peristome teeth are
much twisted. It loves the top of old walls and often associated with it are two
other common mosses, Camptothecium sericeum Kindb. on the sides of the
wall and Bryum argenteum L. at the base, often a kind of zoning. The former
is a lovely species, clothing trunks of trees, walls and rocks with thick shaggy,
golden-green fleeces. It fruits in the spring and although dioecious, the rather
large erect capsules are often produced in abundance. Bryum argenteum is
easily known by its silvery foliage, due to the fact that the upper half of each
leaf is quite colourless and hyaline. My best specimen of this moss, covered
with pendulous capsules, I picked up by the side of a bomb site in Aldersgate
Street in the City of London. The following, which I came across in an old
book on British Mosses is very descriptive: —
"One old populous green wall
Tenanted by the ever-busy flies,
Grey crickets and shy lizards and quick spiders,
Each family of the silver-threaded moss—
Which, look through near, this way, and it appears
A stubble field or a cane brake, a marsh
Of bulrush whitening in the sun: laugh now!
Fancy the crickets, each one 211 his house,
Booking out, wondering at the world—or best
Yon painted snail with his gay shell of dew,
Travelling to see the glossy balls high up
Hung by the caterpillar, like golden lamps."
Browning. Paracelsus.
The other moss, which we found on Dr. Allen's tomb, is not quite so
common. It was Orthotrichum diaphanum Schrad., occurring in dense cushions,
usually on trunks of trees but more rarely on walls or on the ground. It has
silvery white hair points to its leaves and its seta is so short that the oblong
pyriform capsule is hardly raised above it. Dr. Watson in his book says that
it "seems to have a preference for the neighbourhood of human habitations,
perhaps because it is nitrophilous".