See, on the trunk of that towering _Cedrela_, a round hole, out of which a large Beetle is in the act of emerging. It is a noble _Buprestis_, encased in glittering mail, of the most refulgent metallic splendour, crimson, gold, and green. Can we find any clue to his age? Yes: the white grab has rioted and fattened in its burrows in the timber of this tree for many years; ever gnawing away with its horny auger-like jaws the solid wood in tortuous galleries, which constantly enlarged, as it progressively grew, while its wake, as it advanced, was partially filled by its ordure. The old tree is, no doubt, perforated, through and through, by its winding corridors, as large as your middle finger. As soon as the vermin had passed this his nonage, which, as I say, may have occupied a dozen years at least,[71] he sank into his short pupa-sleep, and here we see him paying his first visit to the light of day. True; this is his first experience of daylight, and indeed of anything; for all the pupa-sleep and the larva-labour were prochronic in this case. The Beetle is just created. Hark to that hollow roar! There is no mistaking that majestic sound. It is the voice of the many-sounding sea. Yonder through the trees we catch a glimpse of its shining face, and here we are at the verge of the cliffs, against whose feet the waves are breaking in white foam. We will clamber down to the rocks. In this weed-fringed tide-pool there is a fine specimen of the Shore-crab (_Carcinus moenas_). It is a male just arrived at the perfection of adult age; its carapace smooth and wholly dark-green in hue, its under parts rufous orange. Its claws. are large and sharp; and the promptitude with which it presents these formidable weapons, extended to the utmost, shows how conscious it is of its warlike powers. To all appearance this Crab is several years old;[72] I mean in this his present perfect or imago form. When this form was first assumed, the diameter of the carapace was not more than an eighth of an inch; it is now two inches; a great many periodical sloughings of the crust must have occurred to accomplish this sixteen-fold increase. But four distinct metamorphoses were passed before the commencement of this form. There was the Grapsoid form with the outline of the carapace nearly parallel-sided, and the dentations on the sides. Before this there was the Megalopa form, with the carapace ovate, and the abdomen projecting behind. Before this there was the Zoea form, with the carapace rising into a tall erect spine, sessile eyes, no claws, and the abdomen a slender jointed cord ending in a triangular plate. And before this, there was the egg, which was laid by the mother Crab, and carried by her for a considerable time attached to the false feet of her abdomen. All these evidences of age, clear and unanswerable though they are, are yet fallacious, because the Crab has been created but this morning.