A Conchological Manual, George Brettingham Sowerby [little readers .TXT] 📗

as to include

   all the genera of the Lamarckian Nayades, together with Castalia, which

   are placed in the family Trigonacea, they are all fresh-water shells,

   commonly called fresh-water muscles. The distinctions of the various

   genera into which they have been divided, will be found in their

   respective places, and under the name Nayades. They are all represented

   in figures 140 to 152. Of these fig. 145 to 148, are more generally

   considered as forming the genus Unio.

 

   UNIOPSIS. Sw. A sub-genus of Alasmodon. Sw. p. 382.

 

   UNIVALVE. (_Unus_, one; _valva_, valve.) A shell consisting of a single

 piece, as distinguished from Bivalves and Multivalves, which are

   composed of two or more principal pieces. Spiral shells having an

   operculum, are called sub-bivalves by some authors.

 

   UPPER-VALVE. The free valve in attached bivalves.

 

   UVIGERINA. D'Orb. A genus of microscopic Foraminifera.

 

   VAGINA. Megerle. SOLEN _vagina_, Auct.

 

   VAGINULA. (_A little sheath, the husk of corn._) _Class_, Pteropoda,

   Lam.--_Descr._ Pyramidal, slightly inflated in the centre, thin,

   fragile; aperture oblong, with the edges turned slightly

   outwards.--_Obs._ The little shells of this genus, which are only known

   in a fossil state, differ from Cuvieria in being pointed at the

   extremity. Found in the tertiary beds of Bordeaux. V. Daudinii, fig.

   225.

 

   VAGINULINA. D'Orb. A genus of microscopic Foraminifera.

 

   VALVATA. Müll. _Fam._ Peristomata, Lam. Cricostomata, Bl.--_Descr._

   Thin, turbinated; spire short, composed of from three to six rounded

   whorls; aperture circular; peritreme acute, entire; operculum horny,

   spiral.--_Obs._ This genus of small shells resembles Cyclostoma, from

   which the recent species may be known by the horny texture of the

   external surface, being fresh-water shells. The fossils of course

   belong to the fresh-water formations. V. piscinalis, fig. 322. Europe

   and North America.

 

   VALVES. (_Valva_, a door, a folding piece.) The two pieces composing a

   bivalve shell, which close upon each other, turning upon a hinge

   consisting of a ligament, cartilage, and teeth. See BIVALVE,

   MULTIVALVE, and UNIVALVE.

 

   VALVULINA. D'Orb. A genus of microscopic Foraminifera.

 

   VARIX. (_A swelling vein._) A varix is formed on the outer surface of a

   spiral shell, by the thickened, reflected edge of a former aperture,

   after fresh deposits of testaceous matter have increased the size by

   adding to the growth of the shell beyond it. In this manner there are

   frequently many varices, or edges of former apertures, in various parts

   of the spire and the body whorl. They are sometimes placed at regular

   distances from each other, as in Harpa, fig. 419; sometimes

   _continuous_, as in Ranella, fig. 394; sometimes _discontinuous_, as in

 Triton, fig. 398; sometimes _ramose_, as in Murex, fig. 395; sometimes

   _simple_, as in Scalaria, fig. 351; sometimes _spinose_, as in Murex

   spinosus. The term _varix_ has also been applied to any swelling ridge,

   such as that on the lower part of the columella of Ancillaria, fig.

   456.

 

   VELATES. Montf. NERITINA perversa, Auct. Fig. 326.

 

   VELLETIA. Gray? A genus described as differing from ANCYLUS in being

   dextral. VELLETIA lacustris, ANCYLUS lacustris, Auct. fig. Sowerby Gen.

   fig. 2.

 

   VELUTINA. Auct. _Fam._ Macrostomata, Lam.--_Descr._ Sub-globose,

   covered with a velvety epidermis; spire short, composed of two rapidly

   enlarged ventricose whorls; aperture large, sub-ovate; peritreme thin,

   entire, separated from the last whorl; columella tortuous,

   thin.--_Obs._ This shell does not resemble any other genus in the

   family. Fig. 337. Northern Seas.

 

   VENERICARDIA. Lam. A genus composed of the shorter species of Cardita.

 

   VENERIRUPIS. Lam. (From _Venus_ and _rupis_, a rock.) The oblong

   species of Venus Auct. which live in cavities of rocks and stones. This

   genus is united by Sowerby with some other species of Venus under the

   name Pullastra. V. Vulgaris, fig. 97.

 

   VENTRAL. (_Venter_, the belly.) The margin of a bivalve shell opposite

   the hinge. The under valve in Brachiopodous bivalves is the ventral

   valve. The ventral surface of an univalve spiral shell is that which

   faces the observer when the aperture is placed towards him. The ventral

   part of the whorls of symmetrical convolute shells, is the inner part,

   that which is nearest to the spire.

 

   VENTRAL SIPHON. In symmetrical convolute univalves, is one placed near

   the inner edge of the whorls.

 

   VENTRICOSE. (_Ventricosus._) Swelled, rounded out, (_bombé Fr._) as

   Harpa ventricosa, fig. 419.

 

   VENUS. Auct. (_Goddess of Beauty._) _Fam._ Marine Conchacea, Lam.

   Conchacea, Bl.--_Descr._ Equivalve, inequilateral, sub-globose,

   sub-ovate, transverse, externally rugose, striated, ribbed, cancellated

   or smooth; margins entire, simple, close; hinge with three more or less

   distinct cardinal teeth, diverging from the umbones in each valve;

   muscular impressions two, lateral, distant; palleal impressions

   sinuated posteriorly; ligament external.--_Obs._ This extensive genus,

   including some bivalves of splendour and beauty, justifying the name

   given to it, may be known from Cytherea by the absence of a lateral

   tooth, which is found near the cardinal teeth in the latter. Artemis is

   distinguished not only by its beautiful form, but by the deep angular

   sinus in the palleal impression. Fig. 119, 119 a. Found mostly in

   temperate and tropical climates.

 

   VERMETUS. Adanson. _Fam._ Scalariana, Lam. Cricostomata, Bl.--_Descr._

   Spiral at the apex, irregularly twisted towards the aperture; aperture

   round, small.--_Obs._ This shell resembles the Serpulæ in general

 appearance, although it is regularly spiral near the apex. The animal

   is known to be a true mollusc, rather nearly allied to that of the

   genus Dentalium, which is also placed wrongly in the Lamarckian system.

   Vermetus Lumbricalis, fig. 345. Coast of Africa.

 

   VERMICULAR. (_Vermicularis._) Worm-shaped, tubular, serpentine. _Ex._

   Vermilia triquetra, fig. 7.

 

   VERMICULARIA. Lam. VERMETUS, Adanson; afterwards VERMETUS, Lam.

 

   VERMILIA. Lam. A genus composed of species of Serpula, which are

   attached by the whole length of the shell, no part being free. Vermilia

   triquetra, fig. 7.

 

   VERTEBRALINA. D'Orb. A genus of microscopic Foraminifera.

 

   VERTEX. Apex.

 

   VERTIGO. Müll. _Fam._ Colimacea, Lam.--_Descr._ Cylindrically fusiform,

   sinistral, hyaline; aperture marginated, sinuated, denticulated on the

   inner edge; peristome sub-reflected.--_Obs._ This genus of minute land

   shells, resembles Pupa, but is a reversed, hyaline shell. Vertigo

   pusilla, fig. 293. Europe.

 

   VERRUCA. Schum. CLITIA, Leach.

 

   VESICA. Sw. A sub-genus of Bulinus, Sw. p. 360.

 

   VEXILLA. Sw. A genus of "Nassinæ," Sw. thus described: "General shape

   of _Purpura_, the inner lip flattened and depressed; the outer, when

   adult, thickened, inflected and toothed; aperture wide; picta _Sw._

   Chem. pl. 157, f. 1504-5." Sw. Malac. p. 300.

 

   VIRGULINA. D'Orb. A genus of microscopic Foraminifera.

 

   VITRELLA. Sw. A sub-genus of "Bullinæ," Sw. Lardn. Cyclop. Malac. p.

   360.

 

   VITRINA. Drap. (_Vitreus_, glassy.) _Fam._ Limacinea, Lam. and

   Bl.--_Descr._ Ovate, thin, glassy, fragile; spire short; last whorl

   large; aperture wide, transverse; peritreme simple; columella spiral,

   linear.--_Obs._ This genus of land-shells is not known in a fossil

   state. The recent species are found among moss and grass, in shady

   situations. De Ferussac has divided this genus into Helicolimax, fig.

   263, and Helixarion, fig. 262.

 

   VITULARIA. Sw. A genus of "Muricinæ," Sw. thus described: "General

   habit of _Muricidea_, but the inner lip is depressed and flattened as

   in the _Purpurinæ_; varices simple, nearly obsolete. Tuberculata, Sw.

   En. M. 419. fig. 1. (_Murex vitulinus_, Auct.)" Sw. p. 297.

 

   VIVIPARA. A generic name given by Montfort, and retained by some

   authors for PALUDINA, Lam. on account of the animals being

   _viviparous_, i. e. the young being perfectly formed before they leave

   the ovaries.

 

   VIVIPAROUS. See VIVIPARA.

 

   VOLUTA. Auct. (_Volvo_, to revolve.) _Fam._ Columellaria, Lam.

   Angyostomata, Bl.--_Descr._ Sub-ovate, rather angulated, thick,

   generally tuberculated, smooth; spire short, conical, with a

   mammillated apex; aperture generally angulated, large, terminating

   anteriorly in a deep notch; columella smooth, with several plaits, of

   which the lowest is the largest; outer lip thickened within.--_Obs._

   The genus Voluta, as left by Linnæus, is only characterized by the

   folds on the columella, and includes many shells which, although they

   agree in this respect with the genus, are yet quite opposite to each

   other in all other characters. Thus the Auriculæ, which are land

   shells, and have the aperture entire, are mixed up with others which

   are marine, and have a canal, as Turbinellæ, and the Fasciolariæ, and

   others which have merely a notch, as the true Volutes. This genus, as

   it is circumscribed at present, includes a great number of beautiful

   shells, most of which are rich in colouring. CYMBA and MELO have been

   separated by Mr. Broderip from the genus VOLUTA of Lamarck, for reasons

   stated in their respective descriptions. Fig. 443.

 

   VOLVARIA. Lam. (_Volva_, a shuttle.) _Fam._ Columellaria,

   Lam.--_Descr._ Cylindrical, convolute, spirally striated; spire very

   short, nearly hidden; aperture narrow, as long as the whole shell;

   columella with three oblique plaits; outer lip dentated.--_Obs._ The

   Volvaria are only known in a fossil state, and resemble some species of

   Bulla in general form, but are distinguished by the plaits on the

   columella. Fig. 439, V. concinna.

 

   VOLUTELLA. Sw. (_A little volute._) A genus composed of those species

   of MARGINELLA, Auct. which have the spire concealed, and the aperture

   smooth within. Fig. 438, PERSICULA of Schumacher.

 

   VOLUTILITHES. Sw. (_Voluta_, and [Greek: lithos], _lithos_, a stone.) A

   genus composed of some fossil species of Voluta, which have the plaits

   on the pillar generally numerous, indistinct, and sometimes wanting

   altogether, with a pointed spire. Fig. 436, V. spinosa.

 

   VOLUTION. See WHORL.

 

   VORTICIALIS. Lam. A genus of microscopic Foraminifera.

 

   VULSELLA. Lam. (_A little tongue._) _Fam._ Ostracea, Lau. Margaritacea,

   Bl.--_Descr._ Equivalve, irregular, longitudinal, compressed, oblong;

   umbones separated by a slight area in both valves; hinge with a large

   pit in the centre, containing the cartilage, the ligament being spread

   over the areas; muscular impressions, one on each valve, sub-central,

   oblong.--_Obs._ This genus differs from Ostræa in the equality of the

   valves, and in having a hollow pit in the hinge for the cartilage.

   Vulsella lingulata, fig. 185.

 

   WATERING-POT. Aspergillum, fig. 44, commonly so called on account of

   the resemblance of its perforated termination to that of the spout of a

   watering-pot.

 

   WENTLE TRAP. Scalaria pretiosa, commonly so called.

 

   WHORL. A complete turn or revolution round the imaginary axis of a

   spiral shell. The last whorl is called the _body-whorl_. The whorls are

   described as _non-contiguous_, when they do not touch each other;

   _continuous_, in the opposite case. _Depressed_ when they are flat.

   They are _angulated_, _heeled_, or coronated; _distinct_, or

   indistinct. They are sometimes, as in Cypræa, hidden by the last whorl.

 

   XYLOPHAGA. Sow. ([Greek: xulon], _zylon_, wood; [Greek: phagô],

   _phago_, to eat.) _Fam._ Tubiscolæ, Lam.--_Descr._ Equivalve, globose,

   closed at the back; with a large, angular hiatus in front; hinge with a

   small curved tooth advancing from beneath the umbones in each

   valve.--_Obs._ This shell, which is found in a cylindrical cavity,

   eaten in wood by the animal, resembles Teredo, but has not the shelly

   tube, nor the posterior hiatus. X. dorsalis, fig. 50, 51.

 

   XYLOTRYA. Leach. XYLOPHAGA, Sow.

 

   ZONITES. Montf. A genus formed of Helix Algira, and other similar

   species with depressed spires and large umbilici; included in the

   sub-genus Helicella. Fig. 279.

 

   ZUA. Leach. A genus described as differing from Bulinus in having a

   polished epidermis, and a thickened, not reflected lip. Zua lubrica, B.

   lubricus, Auct.

 

   ZURAMA. Leach. A sub-genus of Helix. H. pulchella, Auct. Gray's Turton,

41.

 

       *       *       *       *       *

 

 

EXPLANATION OF PLATES,

 

AND SYSTEMATIC VIEW OF THE

 

LAMARCKIAN ARRANGEMENT.

 

         _Class_, ANNELIDES.

         _Order_, SEDENTARIA.

         _Fam._ Dorsalia.

 

FIG.

 

Siliquaria anguina. Agathirses, Montf.

 

         _Fam._ Maldania.

 

Dentalium octogonum.

 

Pharetrium fragile, with the outer tube broken.

 

         _Fam._ Serpulacea.

 

Serpula bicarinata.

 

Spirorbis Nautiloides, on sea-weed.

 

Galeolaria decumbens, on a Conia.

 

Vermilia triquetra.

 

Spiroglyphus, on a portion of Patella.

 

Magilus antiquus, old shell. Campulotus, Guild. (from Guerin.)

 

The same, in a young state.

 

Leptoconchus striatus.

 

Stylifer astericola.

 

The same, in a portion of Star-fish.

 

         _Class_, CIRRIPEDES.

         _Order_, SESSILE CIRRIPEDES

 

Tubicinella Balænarum.

 

Coronula Testudinaria. Chelonobia, Leach, Astrolepas, Klein.

 

---- Balænaris. Cetopirus, Ranz.

 

---- diadema. Diadema, Ranz.

 

Chthalamus, Ranz. (from Blainville.)

 

Platylepas pulchra, Leach. One valve separate, showing the inside.

 

Clitia Verruca, Leach. Octhosia, Ranz. Verruca, Schum.

 

Conia porosa. Teraclita, Schum.

 

Elminius Leachii.

 

Catophragmus imbricatus, (from Sowerby's Genera.)

 

 Octomeris angulosus, (from Sow. Gen.)

 

Balanus tintinnabulum.

 

---- Montagui. Acasta, Leach.

 

---- galeatus, Conoplæa, Say.

 

Creusia gregaria. _b._ showing the internal structure.

 

Nobia grandis.

 

Savignium crenatum.   }

                               }

Pyrgoma cancellata.   }   Pyrgoma, Auct.

                               }

Adna Anglicum.       }

                               }

Megatrema semicostata.}

 

        _Order_, PEDUNCULATED CIRRIPEDES.

 

Pentelasmis lævis. Antifa, Lam. a. anterior.

 

Scalpellum vulgare.

 

Smilium Peronii.

 

Pollicipes polymeus. Ramphidoma, Schum.

 

   37*. Pollicipes mitellus. Capitulum, Klein.

 

Brismæus Rhophodius.

 

Lithotrya dorsalis. Absia, Leach, Litholepas, Bl.

 

Ibla Cuvieriana.

 

Heptalasmis Warwickii. Octolasmis, Gray.

 

Cineras vittatus.

 

Otion Cuvieri.

 

         _Class_, CONCHIFERA.

        _Order_, C. DIMYARIA.

         _Fam._ Tubicolaria.

 

Aspergillum vaginiferum. Penicillus, Brug.

 

Clavagella, a fossil species.

 

Teredina personata.

 

Lignite, pierced by Teredinæ.

 

Teredo navalis; _a_, tube