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on our coasts, and has been usually considered among the rarest. The shell is from four to five inches long, and sometimes more, but the animal tenant does not exceed three. The body of this is vermiform, flattish, distinctly annulated, of a reddish-orange colour, stained with irregular blotches, from the opacity of the viscera and their contents. The anterior extremity is obtusely truncate, and on it are placed two large fan-shaped bundles of filaments of a yellowish colour, beautifully marked with scarlet spots. The filaments in each bundle are numerous, and are united at the base into a fleshy stalk, which again is directly connected with the head, on which also some scarlet spots are distributed. Each filament is simple, but pectinated along the internal edge with a close series of short blunt processes, which are not visible without the aid of the magnifier. The anterior third of the body is covered with a thin brown membrane, divided on the ventral aspect, where the margins are free and somewhat undulated; they are also furnished on each side with seven little brushes of bristles, which appear to be partly retractile. These brushes are placed at equal distances; the anterior, perhaps, a little closer; and at the side of each there is a scarlet bar or spot; the bristles in each are very slender, numerous, yellowish, smooth, and acutely pointed. The remaining portion of the body is divided into very numerous short rings, on the sides of each of which there is a thickened puckered spot, something like a beginning tubercle; it is grooved along the back, and tapers to a rather obtuse end, where it is sparingly clothed with some delicate hairs. The ventral surface is convex, smooth, and flesh-coloured; and the anus is terminal, there lying underneath it a long white spot, produced, perhaps, by some dilatation of the intestine. The shell, as we have said, is from four to five inches long, and as thick as a goose-quill. It is cylindrical, o; tapered at the posterior end, where it becomes more or less flexuose, and where it is affixed to the foreign body whence it takes its origin. The attachment in our specimen was broken off. The colour is opaque white, and the smooth surface is partially covered with corallines and smaller Sérpulac. The margin of the aperture is circular, smooth, and even; the other extremity is closed. I kept the individual here figured for several days by me, to observe its motions. The worm would sometimes remain for hours concealed in the shell: and, when it ventured to peep out, the branchial tufts were sometimes slowly and cautiously protruded, and sometimes forced out at once to their full extent. After their extrusion they were separated and expanded, as in the figure, and lay at perfect rest on the bottom

of the plate, in unrivalled beauty, and an object of never failing admiration. The worm, however, seemed never either to slumber or sleep; for, on any slight agitation of the water, occasioned, for example, by walking across the room or leaning on the table, it would at once take alarm, and hurriedly retreat within the shelter of its tube. It was never off its guard, and would often, when lying apparently in calm indulgence, suddenly withdraw, in evident alarm, without a cause but what was gendered by its own natural timidity; for the phantoms of dreams are not, it may be, the visitants only of higher intelligences, but come as they like, in a fearful or cheerful mood, even to these lower things. It never protruded itself farther than is shown in fig. 23. a; and, after becoming weak and sickly, it first threw off one half of its pride, a branchial tuft; and after several hours the other was likewise cast away, when the poor mutilated creature buried itself, still living and to live for a day or so longer, in its own house and cemetery.

The anus is at the posterior extremity, as in other worms; but the remains of its food are ejected from the mouth of the shell, in small egg-shaped pellets. By what contrivance this is done, I do not know: are the pellets forced along the dorsal furrow? The fan-shaped fascicles are its breathing organs; and the brushes of bristles in the sides of the mantle are the organs which enable it to move up and down the tube, assisted, undoubtedly, by the rough spots on the margins of the body. This is traversed down the centre of the back with a vessel filled with red blood, and which sends off minute branches to almost every ring.

Mr. Berkeley has attempted to draw a distinction between Sérpula arundo and tubulària. The former, he says, may be known “ by its more slender form and delicate substance; neither is the aperture expanded, as in S. tubulària. The animal differs from S. tubulària in its oblong dorsal area; while that of the latter is much attenuated behind; and in the absence of the operculum.” Now, if we turn to Montagu, the original describer of S. tubulària, and whose name therefore ought to be retained, we shall find him telling us that the animal has no operculum ; and his description of it agrees exactly, so far as I am able to judge, with Mr. Berkeley's. Indeed, it seems to me, that this very acute and excellent naturalist has confounded the S. tubulària of Montagu with the S. vermicularis of authors : for, on this supposition, his remarks on their distinctive characters will be found perfectly correct and decisive.

Berwick upon Tweed, Feb. 19. 1833.

ART. VI. Illustrations of some Species of British Animals which

are not generally known, or have not hitherto been described. By C. M.

{"s Segnius irritant animos, demissa per aures,
Quam quæ sunt ulis subjecta fidelibus," Hor.

“ What we hear,
With weaker passion will affect the heart,
Than when the faithful eye beholds the part.”

Francis's Translation.] Sir, I shall feel gratified if the accompanying contributions to the British Fauna, “a very short paper and very long drawings,” should meet with your approval, and obtain a place in your journal. Believing that natural history will, in this country, be much more advanced by presenting aocurate sketches of its objects, than by the most voluminous descriptions unaided by them, I shall, confident in the attention I pay to the delineation of those I forward, continue to supply you, from time to time, with such of the animals I meet with as appear to me totally new. I am, Sir, yours, &c.

C, M.

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Asci'dia? Geʼmina. (fig. 24.a) - Body coriaceous, elongate, cylindric, adhering to the rocks by 5 or 6 roots, of a greenish brown colour, surmounted superiorly by two mammiform processes (6), each with a terminal orifice (c) surrounded by 5 oval orange marks. These processes are retractile, but easily made to protrude by pressing the body; and, on continuing it, water is projected in jets from both orifices. It adheres very strongly to the rocks, a number of them being generally found within the limit of a few inches.

VOL, VII. - No. 38.

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Ascidia? HOLOTHU'Ria? A'NCEPs. (fig. 25. a) — Sessile, elongate, irregular in form, obscure greenish yellow, one of the apertures lateral, erect, subterminal. Mouths crateriform, with 8 or 9 segments, from each point of union a row of bright yellow oval dots leading directly to the orifice, which, on pressing the body, emits a jet of water. The interior structure was not examined, so that no opportunity occurs of referring it to its proper position. It appears to approach in form to Ascidia prùnum. Dredged up off Carrickfergus, Belfast Lough, August, 1811. (b, c, Views of the mouth, magnified.)

26

6

b, The same magnified.

a, The animal of the natural size.

C, A profile of the anterior portion magnified.

.“ An atom is an ample field.” CowPER. Na'is Lin. SERPENTINA Gmel. (fig. 26. a) — Hyaline; the convolutions of the intestinal canal obvious. Two dark spots mark the position of the eyes, which seem made up of numerous irregular black points. Mouth immediately beneath the eyes. The snout rounded. A single row of simple spines is protruded from the belly at the will of the animal; a sheath, easily distinguishable, receives them when retracted. The intestinal canal continues in constant action.

If this be Nàis serpentina, and I am disposed to believe it is, it agrees indifferently with the generic character of Lamarck, and the specific of Müller. The former describes the

mouth as terminal, while in mine it recedes considerably from it; the setae lateral, instead of a single ventral row, and the body flattened, instead of cylindric. Müller's description, and his figure does not agree with it, is “setis lateralibus nullis, collari triplici nigro.” Mine is totally deficient in the latter quality, but agrees with the former, though possibly in a different sense from that intended by Müller. It was found entwined round the bracteas of Châra fléxilis.

LUMBRI cus? CLITE'LLIo Savigny? PELLU cIDA. (fig. 27. a) —Minute, hyaline, with porrectile setae, one series on each side of the body, retractible at the will of the animal, within a sheath, which can be distinguished, exterior to the intestinal convolutions. Neither eyes nor mouth is apparent. The rings are strongly marked anterior to the position of the sexual organs, and from each of them proceed 2 lateral setae, which are, at e, exhibited retracted : they were exserted at each violent movement of the animal, or about once every 20 seconds. a Represents the animal of the natural size; b, magnified; c, the anteal extremity; d, the anal, with the setae shot out. It was found among moss. The Lumbricus minūtus of Fabricius and Müller is marine, else the description answers tolerably.

ART. VII. A Description of a Mode, practised by M. Klotzsch, of
drying Specimens of Fāngi for Preservation in Herbariums. By
WILLIAM CHRISTY, Jun. Esq., F.L.S., &c. &c.
Sir,
IF the following brief notice of an easy and successful mode

of preserving Fāngi should be deemed worthy of a place in

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