Grey bonnet shells and fig snails abound on a broad flat that rises off the eastern front of a reclaimed wilderness, a seaboard with no passage to entry but a long march through coastal wasteland or a costly sail under naval gaze. Many of these robust gastropods can be detected by crude breaks in the continuum, smudges on a clean plane that betray the presence of a near-buried mollusc. Others lie on the sand, caught by surprise, as it were, by waters that ran off even as the animals emerged to commence their evening hunt. The cassids, which occur here in numbers that grow with the falling day, are polished fortresses, smooth and shiny helmets that resist the grip of swifter hunters and impose a fatal burden on sand dollars, whose bodies litter this shoal, sliding just under the surface and sifting the grains for organic remains. Phalium also digs in, but probably only as far as is required to elude diurnal predators or reach entombed discs. Sharp spines projecting from the forward edge of the outer lip may provide an added line of defence, giving the snail time to withdraw into its whorls and plug its aperture with a flimsy yellow door.
Ficus is also said to consume sea urchins, but is built for a slightly greater turn of speed which may allow it to snare other benthic creatures. Though not in the league of olivids and moon snails, which plough through the silt with juggernautal ease, its shell appears better adapted for fossorial pursuit. Instead of thickened walls, the spiral is reinforced by fine corrugations or pleats that add a measure of stiffness to an otherwise brittle coil. The animals, which lack an operculum, are reported to be incapable of fully retreating into their shell; survival hence hinges on sacrifice, in the partial loss of a mantle fringe that envelops much of the sculpture and help to shield from sight a minuscule head with two pinprick eyes. Tattered shawls drape some individuals, exposing the pale feet of thorny encounters that justify such extravagance and reward hasty crabs with but a slice of papery tissue.
Countless other small, shelly fauna inhabit this shore, out of sight for the most part save when rogue waves dislodge a seam of life or chip away at the topmost layers to reveal laggards that failed to hit safer depths. Those that do not hasten to plunge back in may succumb to ghost crabs that stalk the higher reaches of the beach and flee to the surf when they spy eminent threats; clams on the lower strand may sustain waders in their winter refuge, brave the drills of heavy-footed naticids or face the crushing teeth of nocturnal crabs. Sleek asteroids also roam these flats, sowing terror among button snails as they seek out bivalved prey. Clad in beige or shorn of pigments that would stand out against a bed of rippled brown, sea anemones with invisible tentacles launch sessile assaults on passing fish or shrimp.
The cnidarians, for all their ability to sting, stun and subdue fiercer creatures, may themselves become the victims of a blotchy slug with a culinary interest in soft polyps and small polychates. With a generous tread and broad, shovel-like head, Euselenops luniceps possesses the means to putter through loose sediment, revealing little of its body but white-tipped rhinophores and a posterior siphon that draws fresh water to its gills. A row of papillae under the oral veil help to detect invertebrate matter, which the slug overpowers by means unknown and which belie its dumpy, rotund form. Pressed, the animals may spring from the bottom with surprising vigour and flap their mantle at length, but the strokes have little influence over their trajectory and do no more than provide a random lift, enough perhaps to steer the slugs from non-pelagic threats.
Shallow depressions sheltered from the full brunt of storms by curving bars and within reach of polarised rays, in which seaweed with globular foliage have settled, harbour another naked snail, one much smaller than the burrowing giants and ill at ease with forays over bare sand. Sacoglossa, the sapsuckers, flourish on beds of Caulerpa, whose walls they puncture before imbibing a stream of cytoplasm, which nourish the slugs and, if left undigested and sequestered into new quarters, supply their hosts with the by-products of solar power. Sarcoglossans are often shell-less, but not a few, such as Volvatella and Oxynoe, continue to lug fragile bubbles on their back, while Berthelinia and other juliids have evolved hinged shelters that recall the valves of clams and mussels.
Lobiger viridis also wields a shell of light build, which protects the gills but leaves other parts undefended. Disguise usually suffices, however, to hide the inch-long slugs as they glide over a tangle of dirty green filaments. The effect is enhanced by two pairs of 'tendrils', sinuous parapodia that resemble fragments of plant matter but unfurl when disturbed to draw unfriendly eyes towards brightly coloured terminal patches and secondary processes. Some have compared these lobes to the wings of butterflies, but it seems unlikely that the animals can propel themselves through the water as depicted in old journals given to flights of submarine fancy. Rather, these organs of excess serve as barriers to hostile entry, stores of reserves from times of plenty that may be cast off as security, expendible surpluses to requirements, against greater losses on a shore which rose with the tide and whose fate is tied to the fortunes of an island with few limits to growth at all costs and quite ill at ease with the immeasurable burden of natural pleasures.
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