Animal soft, elongated, vermiform, naked or inhabiting a tube, which it never entirely quits; the body furnished either with segments or transverse wrinkles; often without a head, eyes or antennæ; without articulated feet, but most of them having in their place bristly, retractile knobs, disposed in lateral rows: mouth subterminal, either simple, orbicular, with lips, or in the form of a proboscis; often with jaws, a knotted longitudinal medulla, and nerves for sensation and motion; the blood red, circulating by means of arteries and veins: respiration by external or internal branchiæ, which are sometimes imperceptible. Four Families.
Animal. The gills, or respiratory organs dorsal, or disposed lengthways on the body.
Shell. Supposed to be tubular. One species.
Arenicola piscatorium.
Animal. See Arenicola.
Shell very thin, conical, tubular, involuted in a spiral manner, loosely and irregularly; aperture circular, sharp edges, interrupted in the middle by a notch, extending like a slit through the greater portion of its length, and stopping abruptly at some distance from the summit. Inhabits the Indian seas. Eight species.
Animal. Respiratory organs not determined, supposed to be at the posterior part of the body.
Shell. Tube thin and slender, open at both ends, encrusted externally with sand and fragments of shells. One species.
Clymene amphistoma.
Animal. Body elongated, conical, sub-vermiform, enveloped in a fistula mantle as far as the anterior third, and ending in a bourrelet pierced in its middle by an orifice with fringed edges; foot altogether anterior, proboscidiform, terminated by a conical appendage, contained in a kind of cup with festooned edges; head distinct, oval, with a terminal mouth in the middle of a digitated lip; a pair of lateral jaws, formed each of two little oval shells garnished with points.
Shell. Tubular, regular, symmetrical, slightly curved longitudinally, tapering gradually to the rear, and opening in a round orifice at each end. Inhabits the British seas. Twenty-one species.
Animal. Respiratory organs in general known, and disposed at or near the anterior part of the body; not separated or covered by an operculum.
Shell. A membranous papyraceous tube in the form of a reversed cone; unfixed; exterior covered with sandy adhesions. Two species.
Animal. But slightly differing from the Pectinaria.
Shell. Tubes numerous, united in a common mass, composed of agglutinated particles of marine substances, cellular at the base; orifice expanded. Found in the Indian Ocean. Two species.
Animal. Body tubicular, elongated, cylindrically depressed, attenuated posteriorly; a row of nodulous and setiferous papillæ on each side; numerous filiform, twisted tentacula surrounding the mouth.
Shell. An elongated cylindrical and membranous tube with lash-like appendages at the end; covered with adhesions of sand and shells. Inhabits the coast of New Holland. Four species.
Animal. Body tubicular, elongated, cylindrical, attenuated behind with many annulated segments.
Shell. An elongated cylindrical tube growing thinner towards the base, of a tough membranous texture, and generally without adhesions. Mediterranean sea. Seven species.
Animal. Gills or respiratory organs separated or covered by an operculum.
Shell. A testaceous tube turned spirally on a horizontal plane, the lower portion of which is attached to marine substances, generally fuci: opening of the tube terminal, rounded or angular. Found on Algæ on the British coast. Six species.
Animal. Body tubular, elongated, depressed, and attenuated behind; segments numerous and narrow; small bundles of awl-shaped bristles in a single row on each side.
Shell. A solid calcareous tube, brown, purple, yellow, tawny, pink, white, or tinged with green. The shells are irregularly twisted, in clusters, and affixed to other substances. Inhabits the coast of Britain. Twenty-six species.
Animal. Body tubicular, elongated and attenuated towards the posterior part, and provided superiorly with a simple testaceous orbicular operculum.
Shell. A testaceous cylindrical tube, narrowed in the rear, twisted, and adhering by the side to marine substances, aperture round, the margin armed with from one to three teeth. Inhabits the British coast. Nine species.
Animal. Distinguished from the vermilia by a very peculiar operculum.
Shell. In groups, testaceous, cylindrical, subangular, wavy, adhering by the base, and open at the summit; aperture orbicular, terminated on the side by a spatular tongue; operculum orbicular, squamose, and consisting of from five to nine testaceous parts or valves. Inhabits the Indian seas. Two species.
Animal. Unknown.
Shell. Usually found imbedded in a species of Madrepore. Base bent into a spiral form, oval, with four contiguous, convex volutions (the last of which is the largest), and prolonged into a straight waved tube, convex above, carinated beneath. Inhabits the sea at the Isle of France. Two species.