"What is it, sir ?" "A pholas," he answered.

"It is one of the most curious burrowing animals known, and has been a puzzle to naturalists for years, until Gosse discovered its secret, as to how it succeeded with its soft and tender shell in penetrating into the hardest rocks, within whose substance it is frequently found completely buried, so that, like the `Fly in Amber,' one wonders how it ever got there!" "What did you say it was ?" asked Mrs Gilmour.

"A `fowl,' sure?
Faith it's a quare-looken' bird, Cap'en dear!" The Captain smiled, but he was not to be tempted away from his hobby.
"The pholas, I said, ma'am," he replied.

"The `pholas dactylus,' as scientific people call it, which, until Gosse, as I said, discovered its mode of action, was quite a puzzle to every one; although, now that the mystery is out, all wonder it was not cleared up before! If you look at the head of the shell, you'll see it is provided with a regular series of little pointed spines at the end of the upper portion.

These spines are of a much harder material than the main part of the shell, and are fixed into it, as you could notice better with a microscope, just in the same way as the steel points for the notes of any air are attached to the barrel of a common musical-box, projecting like so many teeth." "Yes, I can see them," observed Bob, who was listening attentively.
"Look, Nell!" "Well, then," the Captain went on, "besides this toothed head of his, the animal is provided with a sucker at his mouth, by which he can hold on to any wooden pile or stonework he may wish to perforate so as to make his nest inside; and, gripping this firmly with his sucker and working the head of his shell slowly backwards and forwards with a sort of circular rocking motion, he gradually bores his way into the object of his affections, getting rid of the refuse he excavates by the aid of a natural siphon that runs through his body, and by means of which he blows all his waste borings away--curious, isn't it ?" "Very," said Mrs Gilmour; while the children, equally interested, wanted to learn not only all the Captain could tell them of this peculiar little animal, but also everything he knew of the other wonders of the shore.