A Whistling Woman Read Online Free PDF Page A

thistles were glittering prisms, full of many-coloured lights. And across the wet turf, over the dry-stone walls, the snails slid fluently, creating an intricate net of silvery ribbons, their shells glistening with water, their dove-grey translucent bodies glistening with their own secretions, their fine horns wavering before them, testing the air, peering quietly around. Their shells were variegated and lovely, some a delicate lemon, some a deep rose, some a greenish soot-black, some striped boldly in dark spirals on buff, some with creamy spirals on rose, some with a single band of dark on gold, some like ghosts, greyish-white coiled on chalk-white. Most of these were
Cepea nemoralis
and had rich black lips, but some—not many—closely resembling the
nemoralis
in other ways, were white-lipped
Cepea hortensis
. Several also bore glossy blue, or green, or crimson dots on their shoulders, placed there by the latest group of researchers to track their movements and their fates.
    The snail populations of Dun Vale Hall, and the surrounding moorland of the rich limestone of Gungingap, had been studied by several generations, beginning with a Victorian vicar, Richard Hunmanby, and an Edwardian schoolmaster and distinguished amateur conchologist, Joseph Mann. Luk Lysgaard-Peacock and Jacqueline Winwar were attempting to study the population genetics and the biological diversity of the creatures who obligingly carried their histories, written like hieroglyphs, on the coiling, brittle houses on their backs. They compared the incidence of one, two and three stripes, of dark and light shells, with the records of their predecessors. In the days of Hunmanby and Mann, the snails had been known as
Helix,
not
Cepea, hortensis
or
nemoralis
. Hunmanby had been of the opinion that
nemoralis
and
hortensis
were distinct species. Mann was not sure. He had observed that the creatures lived together and intermingled, but had more than once observed large numbers of both kinds clustered, intertwined, high in the branches of beech-trees.
    â€œMy object in climbing amongst them—in the case of those individuals who were very high in the trees I used a pair of powerful field glasses, discretion being the better part of valour—was to ascertain whether matrimonial alliances between these two forms are usual or not. In one avenue of beech-trees, decked with shells, I counted sixty happy couples, twenty-five of which were
hortensis,
the rest
nemoralis
. In all my observations I saw no single instance of such cross-marriages—the ‘black-mouths’ invariably paired with ‘black-mouths’ and ‘white-mouths’ with ‘white-mouths.’ There is also the smaller variety
H. hybrida,
smaller with a pink or brown mouth and rib, which I have never observed to mate at all.”
    The object of Jacqueline Winwar’s thesis—which was nearly completed—was to ascertain whether the changes in the populations—fewer striped shells, more single-coloured—were influenced more by heredity and Darwinian selection, or by immediate changes in the environment. Did woodland dappling favour stripes? What effect was the recent diminution in the thrush population having? Luk Lysgaard-Peacock’s concerns with population genetics were larger and more varied, but his field-work with these snail populations had been continuous for some years now, and was beginning to show some interesting (if anomalous) patterns.
    They worked well together, moving quietly across the wet ground, charting the numbers and positions of this and that colour and form. They worked at snail-level and snail-speed, interrogating tufts, turning over stones. Jacqueline stopped to count, to piece together, the smashed and picked-out shells by the thrush’s anvil—there was a preponderance of dark and striped, including several green-spots which had been marked not in the wood, but in the hedgerow between the field with the hen-houses