be a specimen of the
"Chama Gigas." The shells were nearly three feet in length, and
curiously marked and clouded. Johnny had slipped from the slimy edge of
the chasm, and happened to fall fairly into the expanded jaws of the
chama, which, had instantly closed upon him. If the water had been
deeper, the consequences might have been serious, as there are instances
of persons being drowned, by having their feet caught in the vice-like
grip of this formidable bivalve.

Not far from the scene of Johnny's mishap, was a green spot upon the
reef, where a group of young trees seemed to spring up out of the bare
coral. On approaching the place, we found that a little island, about
the size of Palm-islet was there in process of formation.
Notwithstanding the exposed and barren character of the locality, and
the scantiness of the soil, which was not anywhere a foot in depth. It
was covered with a thrifty vegetation, among which were several
well-grown-palms, a group of young casuarinas, and some ferns and
tournefortias. Nor was this embryo islet destitute of inhabitants. The
trees were at this hour filled with aquatic birds, and I observed among
them one remarkable species, long-bodied, and slender, like swallows,
with red bills and feet, white breast, and slate-coloured wings; these,
instead of perching, like the rest of their feathered associates, upon
the trees, nestled in the concavity of the long palm-leaves, far enough
from the stem, to be rocked gently by the undulating motion of the leaf,
which a breath of wind, or the slightest stirring of the birds in these
swinging nets was sufficient to produce. But by far the most numerous
and singular portion of the population of the islet, consisted of a
species of large land-crab, inhabiting burrows hollowed out beneath the
roots of the trees. Great numbers of them appeared to be bathing or
sporting in the shallow water on the lagoon side of the islet, but, at
sight of us, they scrambled off to their burrows with a degree of
agility that could hardly have been expected from such clumsy-looking
creatures. Owing partly to this unlooked-for rapidity of locomotion,
and partly to a natural shyness and hesitation which we felt about
handling them rashly, (their pincer-like jaws, with half a dozen pairs
of which each individual seemed to be provided, having a rather
formidable appearance), they escaped before we could capture even a
specimen. Johnny forthwith posted himself in