l68 MARINE NATURAL HISTORY OF THE COLNE ESTUARY.
Amongst the most common objects are Philine (a Gasteropod
with internal shell), the common Shore-Crab, the Hermit Crab,
two species of Spider Crab, Shrimps, Prawns, and the two
"Star-fishes," Uraster and Solaster. The Swimming Crab is not
common. Past the 4th Beacon, where the bottom is sandy the
common Sand-stars, Ophiura texturata, are very common, and in
some places Alcyonidium glomeratum, called "Pipe-weed" by some
fishermen, was, and probably still is, very abundant.1
Sometimes amongst the Algae dredged for my aquaria, there
must have been small individuals of a Nereis, which builds tubes
amongst them, and afterwards grew to a fair size ; whereas, in
other years none of these occurred, but, on the contrary, a con-
Brightlingsea Harbour and Mouth of the Colne.
siderable number of a species of Heteronereis which I had caught
quickly swimming on the surface of the water at Queenborough,
but never could find where it usually lived. It thus turns out
to build tubes amongst the larger Algae and to be common only
in particular years and it occasionally swims at the surface.
Beyond Oysters, Mussels, Whelks, Dog-whelks, Periwinkles,
Rissoa and a small Trochus, the number of Testaceous
Mollusca dredged alive is extremely small ; but, judging from the
dead shells, a number of other species must now live, or did live
not long ago, somewhere in the district. Amongst the most
striking is a somewhat pretty bivalve, perhaps Tapes decussata,
which can be procured alive from the mud off Mersea.
1 This species is often cast up in great quantities after a high tide, on to the shore at
the "Hard," at East Mersea.—W. Cole.