One morning I found him on his back, his body bent upward, with the edge of the base turned in all round towards the centre.  Did you ever see an apple-dumpling before it was boiled, just as the cook was pinching the dough together?  Yes?  Then you may imagine the appearance of my Natica; but no greening pared and cored lay within that puckered wrapper.

Two days passed with no visible change; but on the third day the strange gasteropod unfolded both himself and the mystery.  From his long embrace fell the shell of a Mactra, nearly as broad as his own.  Near the hinge was a smooth, round hole, through which the poor Clam had been sucked.  Foot, stomach, siphon, muscles, all but a thin strip of mantle, were gone.  The problem of the Natica’s existence was solved, and the verification was found in more than one Buccinum minus the animal,—­the number of the latter victims being still an unknown quantity.

Not in sport had Natty driven the plough, not in idleness had he hollowed the sand.  He sought his food in the furrow, and dug riches in the mine.

Doubtless he killed the bivalve,—­for until the time of its disappearance it had been in full vigor,—­but with what weapon?  And whereabouts in that soft bundle was hidden the wimble which bored the hole?

A few days after, a Crab, of the size of a dime, died.  Nat soon learned the fact, and enveloped the crustacean as he had done the mollusk.  Thirty hours sufficed to drill through the Crab’s foundation-wall, and to abstract the unguarded treasure.

Every week some rifled Trivittatum tells a new tale of his felonious deeds.

His last feat was worthy of a cannibal, for it was the savage act of devouring a fellow-Natica.  You might suppose that in this case the trap-like operculum would afford an easy entrance to one familiar with its use; but, true to his secret system, the burglar broke in as before.  How did he do this?  Did he abrade the stone-work with flinty sand until a hole was worn?  Did he apply an acid to the limy wall until it opened before him?  Who can find the tools of the cunning workman, or the laboratory where his corrodents are composed?

Some rods farther south, the shore is covered with smooth stones, and there you may find the Limpet in great numbers.  Patella is the Latin name, but children call it Tent-Shell.  Oval at the base, it slopes upward to a point a little aside from the centre.

In this locality they are small, seldom more than an inch in length.  At first, you will not readily distinguish them, they are so nearly of the color of the stones to which they are attached.  This is one of those Providential adjustments by which the weak are rendered as secure as the strong.  Slow in their movements, without offensive weapons, their form and their coloring are their two great safeguards.  The stones to which they adhere are variegated with brown and purple blotches of incipient Coralline, and the shells are beautifully mottled with every shade of those colors.  Some are lilac, heightening nearly to crimson; others are dark chocolate and white, sharply checkered.