wonder that it never capsizes, but, on looking more closely at it, we see depending from its bottom a great bunch of wrinkled strings, some of which are blue and others crimson; these help to keep it steady. These pendent organs, which differ considerably among themselves in form and appearance, have, doubtless, diverse functions; but some of them are known to be endowed with a most terrific power of stinging, and are, therefore, concluded to be prehensile tentacles, whose use is to arrest, benumb, and hold the fleeting prey.

In another tropical genus we find a new form and a new principle of motion. A number of delicate threads, called cirri, hang from the under surface, which are considered as the swimming organs, and the animals constitute the order Cirrigrada. We are not sure, however, whether these ought not rather to be grouped with the last mentioned, the cirri being probably analogous, both in structure and function, to the pendent tentacles of Physalia. These, too, are dauntless mariners-oceansailors of an antiquity long prior to the period when he of the "robur et as triplex" acquired poetic fame. We once met with a few specimens of the "Sallee-man"* (Velella) on the shore of Portland; but we will use the elegant language of Professor Jones to describe it :

"Its body is a flattened disk, which floats upon the bosom of the sea; and as it swims we see depending from its under surface a great number of small suckers, wherewith to suck up food as it moves slowly onward. Pro

* The popular names given to those oceanic Medusæ point to a time when the maritime power of Portugal and Morocco was more formidable than it is

now

jecting from the upper surface is the broad, flat sail—a soft, transparent membrane, but still strong enough for the light boat that bears it.

“But if a sail be given to beings such as these, whose bodies are almost of the same density as the salt water in which they live, and at the same time so soft in their consistency, some provision must be made to float the tiny ship, and keep it buoyant. A mast is likewise needful, and, moreover, ballast must be furnished to secure its steady course, and keep it from capsizing. All these are furnished, and by means as simple as they are efficient. Unlike the other Acalephs, whose body is entirely soft, these species form in the substance of their backs a shelly plate, so thin as scarcely to be visible, and yet so porous that, being filled with air, it is extremely light, so much so as to constitute a float, by means of which the creature swims. Placed vertically on the top of this stands up another lamina of shell, still thinner than the former, planted in the substance of the sail; this forms the mast, and gives sufficient strength and stiffness to enable the thin, filmy sail to stand erect against the wind, which otherwise would be impossible. The ballast is obtained from other sources; small shells and stones are seized by the appendages upon the lower surface of the body, which, from their weight, may serve to trim the little vessel as it scuds along, climbing the billows as they rise and fall, or slowly sailing on the tranquil deep."

*"Nat Hist. of Animals," i. 189.

CHAPTER X.

ECHINODERMATA (Star-fishes).

ON many a shingly beach where the limestone formation occurs there may be found small perforated pebbles, which, rounded and polished by the action of the waves, resemble beads of stone. In the days of Popish superstition, these were supposed to be fashioned by an imaginary "Saint Cuthbert" for the rosaries with which prayers and invocations were meted out by tale. One of the rocky islets that speckle the tempestuous sea of Northumberland, was assigned to the special manufacture of these useful articles :

'— On a rock by Lindisfarn

Saint Cuthbert sits, and toils to frame

The sea-born beads that bear his name."-Marmion.

In the same districts where these occur, the wondering peasantry have often admired what they call Lily-stones, a class of fossils to which modern geologists apply the equivalent term Encrinites; the stony stem, and a crown of rays bending in sigmoid curves, resembling the stalk and elegant bell-shaped blossom of a liliaceous flower.