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out before the problem is solved. In amongst the
Hydrobia ulvae small white triangular shaped bivalves
were found which on identification turned out to be
Abra tenuis. Along the bottom edge of the seawall
rocks Littorina littorea L. was very numerous, several
colour forms being found including red, yellow, brown
and the even commoner black form. Higher up the sea-
wall we found Littorina saxatilis, the rough winkle
distinguished from the edible periwinkle in the lip
of the mouth joining the first whorl of the shell at
right angles and the lip being an even colouration.
The edible periwinkle on the other hand has the lip
joining the shell tangentially and there are chocolate
brown stripes, like a fence, inside the mouth.
Under some of the rocks small crabs, Carcinus maenasL.,
chitons, Lepido-chitona cinereus, and the grey top
shell Gibbula cineraria were found hiding. A few
Slipper Limpets, Crepidula fornicata, a single large
necklace shell, Natica catena,and some valves of
Cerastoderma lamarcki identified later on were found
dead amongst the rocks.
The party then walked back across the sand and mud
flats covered in the mounds of sand formed by the rag
worm, Nereis diversicolor, to a small piece of salt
marsh near where the cars were parked. Signs of
some very large animals could be seen in the salt pans
so we decided to dig one out. What came out quite
shocked some members of the group and certainly
surprised most of us. The lug worm, Arenicola,
is usually some 6"-l' long and some 1/2" wide but this
animal was some 2-2'6" long and an 1" wide at the
head end. It was a dark olive green in colour and
pushed out immense jaws on an invertable proboscis
from its head, which left everyone in no doubt that
if it got near enough to attack it would certainly
inflict a never forgotten wound. We returned it to
its muddy world in the salt pan after most of the group
had seen it. In some of the heavier mud the dead
valves of the borer, Barnea candida L., were found
and on some of the softer mud some Limaponta depressa,
a small black sea slug, were crawling. Amongst