The Naturalist on the Thames | Page 5

some Titania of the waters. A
number of these tiny shells, gathered from below the bridge, lie before
the writer, set on black satin to display the hues. They look at a little
distance like a series of mixed Venetian beads, but of more elegant
form. From whichever side they are seen, the curves are the perfection
of flowing line. The colouring and ornament of each is a marvel and
delight. Some are black, with white spots arranged in lines following
the curves, and with the top of the blunt spiral white. These
"black-and-white marble" patterns are followed by a whole series in
which purple takes the place of black, and the spots are modified into
scales. Then comes a row of rose-coloured shells, some with white
lance-heads, or scales, others with alternate bands of white scales and
white dots. Some are polished, others dull, some rosy pink, others
almost crimson. Some are marked with cream and purple like the juice

of black currants with cream in it. In some the scale pattern changes to
a chequer, some are white with purple zig-zags. And lastly come a
whole series in pale olive, and olive and cream, in which the general
colour is that of a blackcap's egg, and the pattern made by alternate
spots of olive and bands of cream. If these little gems of beauty come
out of the London river, what may we not expect in the upper waters of
the silver Thames?[1] A search in the right places in its course will
show. But these neretinae are everywhere up to the source of the river,
for they feed on all kinds of decaying substances. If the pearl is the
result of a disease or injury, the beauty of the neretina is a product or
transformation from foul things to fair ones.
As the Thames is itself the product and union of all its vassal streams,
an "incarnation" of all the rest, so in its bed it holds all the shells
collected from all its tributaries. Different tribes of shells live in
different waters. Some love the "full-fed river winding slow," some the
swift and crystal chalk-stream. Some only flourish just over the spots
where the springs come bubbling up from the inner cisterns of earth,
and breathe, as it were, the freshness of these untainted waters; others
love the rich, fat mud, others the sides of wearings and piles, others the
river-jungles where the course is choked with weeds. But come what
may, or flourish where they please, the empty shells are in time rolled
down from trout-stream and chalk-stream, fountain and rill, mill-pool
and ditch, cress-bed and water-cut, from the springs of the Cotswolds,
the Chilterns, the downs, from the valleys of Berkshire,
Buckinghamshire, Surrey, Gloucester, Oxford, and Essex, into the
Thames. Once there the river makes shell collections on its own
account, sorting them out from everything else except a bed of fine
sand and gravel, in which they lie like birds' eggs in bran in a boy's
cabinet, ready for who will to pick them up or sift them out of it. These
shell collections are made in the time of winter floods, though how they
are made or why the shells should all remain together, while sticks,
stones, and other rubbish are carried away, it is impossible to say. They
are laid on smooth points of land round which the waters flow in
shallow ripples. Across the river it is always deep, swift, and dark,
though the sandbanks come in places near the surface, and in the
shallows grow water-crowfoot, with waving green hair under water,
and white stems above it. The clean and shining sand shelves down to

the water's edge, and continues below the surface. Here are living shells,
or shells with living fish in them. In the bright water lie hundreds of the
shells of the fresh-water mussels, the bearers of pearls sometimes, and
always lined with that of which pearls are made, the lustrous nacre. The
mealy masses of dry sand beyond the river's lip are stuffed with these
mussel shells. They lie all ways up, endways, sideways, on their faces,
on their backs. The pearl lining shines through the sand, and the
mussels gleam like silver spoons under the water. They crack and
crunch beneath your feet as you step across to search the mass for the
smaller and rarer shells. Many of those in the water contain living
mussels, yellow-looking fat molluscs, greatly beloved of otters, who eat
them as sauce with the chub or bream they catch, and leave the broken
shells of the one by the half-picked bones of the other. There was a
popular song which had for chorus the question, "Did you ever see an
oyster walk upstairs?" These mussels walk, and are said to