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most Annelidans are locomotive organs, in Lycoris, Phyllodoce, and some other Nerëideans1 become a kind of tentacle. The marine Scolopendra of Aristotle most probably belonged to this Order, and many species make a near approach to the terrestrial ones. Like them they are long and often flat, consisting of a great number of segments, some having between two and three hundred, furnished according to the species, with one, two, or three pairs of legs in each; like them also they twist about in all directions when handled, they conceal themselves in close places where they lie in wait for their prey. In one respect some of them add the instinct of the spider to that of the centipede, for they line and sometimes cover the cavities of the rocks which they inhabit with a slight silken web, and thus concealed they watch the approach of some animal, and, suddenly thrusting out the anterior part of their body, seize and devour it.

My late indefatigable and talented friend, the Rev. L. Guilding once found a land species, in an ancient wood in the Island of St. Vincent's, which from its soft body he regarded as a Molluscan, but from its figure, and annulose structure, its jointed antennæ, and seemingly jointed legs crowned with bristles, it3 certainly belongs, as Mr. Gray has remarked, to the present class.

1 Savigny, Syst. des Annel. 9, 12, 13.

2 PLATE VIII. FIG. 4.

3 PLATE VIII. FIG. 1. Mr. G. calls it Peripatus juliformis.

Though it has scarcely a distinct head, its resemblance to the cylindrical myriapods' is very striking. Other species of this Order resemble the Isopod Crustaceans, and some even roll themselves up like one tribe of them.2

These animals have their haunts sometimes in deep burrows and passages under the sea-weed or in the sea-sand. They are so fierce in their habits that some have been styled the tigers of the worms. Some fishes in their turn make them their prey. Many of them, as the seamouse,' are remarkable for the brilliancy of their metallic hues. Perhaps these dazzling splendours, as in the case of some insects, may be of use to them in preventing the escape of their prey. Their forms and instruments of locomotion seem particularly adapted to the situation and circumstances in which they are placed; their legs, which approach the jointed legs of crustaceans and insects, fit them for moving on the surface of the bed of the sea, their oars for swimming in the water, and the long form of many for threading the sinuous paths and burrows in which they have their habitation and place of refuge. So exactly are they fitted by the skilful hand of the almighty and benevolent Architect of all animal forms to live and move in the place he has assigned to them.

1 Julus. L.

3 Aphrodita aculeata.

2 Nereis Armadillo.
Introd. to Ent. ii. 221.

APPENDIX.

SINCE the preceding part of this treatise had mostly passed through the press, I have had an opportunity of consulting some recently published works, which contain accounts, illustrated by figures, of many very interesting animals belonging to several of the Classes of which I have there treated; and all of which more or less demonstrate a presiding Intelligence immediately connected with the globe that we inhabit, and who, viewed under every aspect, evidently careth for us, and all the creatures he has made. I shall select a few of these for the consideration of the reader.

2

I formerly observed' that types representing some of the higher forms of the animal kingdom were often to be detected amongst those belonging to its lowest grade: a remarkable instance of this may be seen in one of Ehrenberg's late works, in which is described and figured a singular Polygastric Infusory, which seems to exhibit the first outline of an Arachnidan3 form; it has 2 Symbolæ Physicæ.

1 See above p. 320.
3 Discocephalus Rotator.

eight locomotive organs or bristles, representing the eight legs of those animals. By means of these organs, this animal, which was found by Dr. Ehrenberg in the Red Sea, performs a double rotatory movement, one by the rotation of the anterior pair, and the other by the three posterior pairs. The motion of these filamentous legs is so rapid that they appear as if, instead of eight, a hundred were revolving, and so form a kind of natural Phantasmascope. Another infusory genus, Bacillaria, seems to prefigure the Salpes," the species at first being concatenated in chains or ribands, and afterwards separating. The animalcules forming this genus have sometimes been mistaken for plants, and the quadrangular form of the associated individuals gives them the appearance of the jointed stem of a plant, rather than of an animal chain. On a former occasion, I alluded to other imitations of the vegetable world exhibited by the polypes, particularly to some of them producing seeming blossoms, consisting, as it were, of many petals. I shall now notice some that represent monopetalous flowers. A genus long known to naturalists, which seems intermediate between the Infusories and the Polypes, named originally by Linné Vorticella, exactly simulates a bell flower with a spiral footstalk. They are often found in fresh water,

1 PLATE I. A. FIG. 6.

3 PLATE I. A. FIG. 4, 5.

2 See above, p. 222.
4 See above, p. 169.

and present no unapt representation of a bunch of the flowers of the Lily of the valley, whence one species has been named Vorticella Convallaria. Some of these have branching, and others simple stems,' but they are all spiral, and capable of being lengthened or shortened at the will of the animal, which is thus enabled to elevate or depress its little blossoms, the mouths of which are furnished with a double circlet of filamentary tentacles, by the rotation of which, like the rest of its tribe, it can produce a food-conveying current to its mouth. Still nearer to the Polypes, with which indeed it is arranged, is another genus representing monopetalous flowers, named by Ehrenberg, who found it in the Red sea, Zoobotryon, or Animal-grape. This singular animal production will scarcely arrange under any of the Orders mentioned on a former occasion, but it may be regarded as intermediate between the Rotatories and the Polypes. Like the latter it is a compound animal, consisting of a naked branching stem; its lower extremity, as may be seen in the figure, appears as if sending forth numerous little radicles, and the branches terminate in ovate germs, from which issue a multitude of animalcules resembling monopetalous bell-shaped flowers, with the mouth surrounded by a filamentous coronet, each sitting upon a

1 See above, p. 166.

2

2 PLATE I. B. FIG. 2. a.

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