A Conchological Manual by George Brettingham Sowerby (best interesting books to read txt) 📕

   Murices, &c.

   RAMPHIDOMA. Schum. POLLICIPES, Leach.

   RAMOSE. (_Ramosus_, branched.) Spread out into branches. _Ex._ Murex

   inflatus, fig. 395.

   RANELLA. Auct. (_Rana_, a frog.) _Fam_. Canalifera, _Lam._

   Siphonostomata, Bl.--_Descr._ Oval or oblong, depressed, thick, with

   two rows of continuous varices, skirting the outline, one on each side;

   spire rather short, pyramidal, acute, aperture oval, terminating in a

   canal at each extremity; outer lip thickened within, crenulated, or

   denticulated, forming an external varix; inner lip spread over a

   portion of the body whorl.--_Obs._ The shells composing this

   well-defined genus, are for the most part covered with tuberculations,

   and granulations, and from the colour and squat shape of some species,

   have been likened to frogs. The Ranellæ are mostly inhabitants of the

   East Indian seas. The few fossil species known, occur in the tertiary

   beds. The two continuous rows of varices skirting the spire,

   distinguish this genus from Triton, which it nearly approaches, and

   into which some species run by imperceptible gradations. Fig. 393, 394.

   Many new species were brought to this country by Mr. Cuming, and are

   represented in parts 84, 85, 88, 89, 92, 93, of the author's

   Conchological Illustrations.

   RANGIA. Desmoulins. GNATHODON, Gray.

   RAPANUS. Schum.? A genus consisting of species of PYRULA, Auct. which

   are thin, much inflated, with short canals. Fig. 389, P. papyracea.

   RAPELLA. Sw. A genus of "Pyrulinæ," Sw. thus described: "Shell

   ventricose, generally thin, almost globose; the base suddenly

   contracted, and forming a short canal, the channel almost obsolete;

   umbilicus large, partly concealed by the inner lip. R. papyracea. En.

   Méth. 436, f. 1." Sw. p. 307. RAPANUS, Schum. Fig. 389.

   RAPHANISTER. Montf. A species of madrepore, described as a shell.

   RAPUM. Humph. TURBINELLA, Lam.

   RAZOR SHELL. A common name by which shells of the genus Solen, are

   known in the market.

   RECTILINEAR. (_Rectus_, right; _linea_, a line.) In a straight line.

   _Ex._ The hinge of Byssoarca Noæ, fig. 132.

   RECURVED. (_Re_, back; _curvo_, to bend.) Turned backwards; the term,

   when applied to symmetrical conical univalves, is used to signify that

   the apex is turned towards the posterior margin, as in Emarginula, fig.

   241.

   REFLECTED. (_Reflected_, to fold back.) Turned, or folded backwards.

   _Ex._ The edge of the outer lip in Bulinus, fig. 282, is _reflected_,

   while that of Cypræa, fig. 445 to 450, is _inflected_.

   REMOTE. (_Remotus_, distant.) Remote lateral teeth in a bivalve shell,

   are those that are placed at a distance from the cardinal teeth. _Ex._

   The lateral teeth of Aphrodita, (fig. 123.) are remote; those of Donax,

   (fig. 108) are near.

   RENIELLA. Sw. A sub-genus of Malleus. Lardn. Cyclop. Malac. p. 886.

   Gray states it to be only a distorted specimen of Vulsella, Syn. B. M.

   RENIFORM. (_Ren_, a kidney; _forma_, shape.) Shaped like a kidney.

   _Ex._ The aperture of Ampullaria, fig. 318.

   RENULINA. Lam. A genus of microscopic Foraminifera.

   REOPHAX. Montf. A genus of microscopic Orthocerata, Bl.

   REPENT. (_Repens_, creeping.) A term applied to those shells, which,

   being attached by the whole length of their shell, give the idea of

   creeping or crawling. _Ex._ Vermilia, fig. 7.

   RETICULATED. (_Reticulatus._) Resembling net-work.

   RETIFERA. Bl. The first family of the order Cervicobranchiata, Bl.

   containing the genus Patella.

   REVERSED or SINISTRAL SHELLS, are those in which the aperture is on the

   left side of the shell, while it is held with the mouth downwards, and

   towards the observer. _Ex._ Balea, fig. 296. Attached bivalves are said

   to be reversed, when the left valve is free, instead of the right; a

   circumstance which sometimes occurs in Chama and Ostrea.

   RHEDA. Humph. HYALÆA, Lam.

   RHINOCLAVIS. Sw. A genus of "Cerithinæ," Sw. thus described: "channel

   curved backwards, in an erect position; inner lip very thick, with a

   tumid margin; pillar generally with a central plait; operculum

   ear-shaped; lineatum. En. M. 443, fig. 3, Vertagus. Ib. f. 2,

   subulatum. Lam. No. 23, fasciatum. Mart. 157, f. 1481. obeliscus, En.

   Méth. 443, f. 4; aluco, Ib. f. 5, (Aberrant,) semi-granosum. Ib. 443,

   RHINOCURUS. Montf. A genus of microscopic Foraminifera.

   RHINODOMUS. Sw. A genus of "Scolyminæ," Sw. thus described: No internal

   groove; shell clavate; the spire longer than, or equal with the

   aperture; the whorls with ridges or longitudinal varices, and rendered

   hispid by transverse grooves; inner lip wanting; pillar with a terminal

   fold; aperture striated; outer lip with a basal sinus. R. senticosus,

   Chem. tab. 193. f. 1864-1866.

   RHIZORUS. Montf. A genus described from a microscopic shell, appearing

   to be a cylindrical Bulla.

   RHODOSTOMA. Sw. A sub-genus of "Turbininæ," Sw. p. 344.

   RHOMBOIDAL. ([Greek: rhomboeidos], _rhomboeidus_.) Having a rhombic

   form, i. e. four-sided; two sides meeting at acute, two at obtuse,

   angles. Conchologists are not very strict in the application of this

   term, for, indeed, a perfect rhomboidal figure could not be found among

   all the testaceous productions of the sea.

   RHOMBOIDES. Bl. A genus described as resembling Byssomya in the shell,

   but differing in the animal. MYTILUS rugosus, Gmelin. HYPOGÆA barbata,

   Poli.

   RHOMBUS. Montf. ([Greek: rhombos], _rhombos_, a rhomb.) A genus

   consisting of species of CONUS, having a rhomboidal or quadrilateral

   form and a coronated spire. _Ex._ Conus nocturnus, fig. 459.

   RICINULA. Lam. (Resembling the seed-vessel of the _Ricinus_.) _Fam._

   Purpurifera, Lam. Entomostomata, Bl.--_Descr._ Sub-ovate, thick,

   tuberculated; spire short; aperture narrow, terminating anteriorly in a

   short canal; outer-lip thickened, denticulated within, digitated

   without; columellar lip spread over a portion of the body whorl, and

   granulated.--_Obs._ This interesting genus is composed of some neat

   little shells allied to Purpura, from which they are distinguished by

   the finger-like branching of the outer lip, and the granulations of the

   columella. Fig. 413, R. Horrida.

   RIGHT. See DEXTRAL.

   RIMULA. Defr. A genus consisting of a minute species of EMARGINULA,

   Auct. which has a fissure near the margin, but not reaching it. R.

   Blainvillii, fig. 243.

   RIMULINA. D'Orbigny. A genus of microscopic Foraminifera.

   RINGICULA. Deshayes. A genus founded on Auricula ringens of Lamarck and

   several small fossils, resembling in some respects Pedipes of Adanson;

   they would belong to Tornatella, were it not for the lips being

   thickened and marginated, fig. 540, A. ringens.

   RISSOA. Freminville. _Fam._ Ellipsostomata, Bl. Melaniana,

   Lam.--_Descr._ Oblong, turrited, acuminated; spire long, consisting of

   numerous whorls; aperture round or oval, pointed posteriorly, dilated

   anteriorly; outer lip slightly thickened, emarginated, operculum

   horny.--_Obs._ The Rissoæ are small white, marine shells, considered by

   some authors as resembling Melaniæ, but placed by Sowerby near the

   Scalariæ. They are principally from the shores of the Mediterranean,

   and are also very abundant on the British shores, as well as the East

   and West Indian. Fig. 346, R. reticulata.

   ROBULUS. Montf. A genus of microscopic Foraminifera.

   ROLLUS. Montf. A genus composed of CONUS Geographus, Auct. fig. 462,

   and other species, rather cylindrical in form, and having a coronated

   spire.

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

   ROSTELLARIA. (From _rostrum_, a beak.) _Fam._ Alatæ, Lam.

   Siphonostomata, Bl.--_Descr._ Turrited, fusiform, thick, smooth or

   ribbed; aperture oval, terminating anteriorly in a long canal,

   posteriorly in a channel running up the spire; outer lip dilated,

   thickened, sometimes digitated, running up all or part of the spire,

   with a sinus near the anterior canal; inner lip smooth, spread over

   part of the body whorl and of the spire. The Red Sea and the Indian

   Ocean produce the few known species of this genus.--_Obs._ HIPPOCHRENES

   is the name given by De Montfort, to those fossil species which have

   the outer lip simple and very much dilated. R. curvirostrum, fig. 412.

   APORRHAIS is a name given to another proposed genus, composed of

   Rostellaria pes-pelecani, Auct. fig. 404. and similar species.

   ROSTRATED. (From _rostrum_, a beak.) Having one or more protruding

   points, as Tellina rostrata.

   ROTALIA. Lam. A genus of microscopic Foraminifera. The same as

   Rotalites of De Montfort.

   ROTELLA. Lam. (_A little wheel._) _Fam._ Turbinacea, Lam.--_Descr._

   Orbicular, generally smooth, shining; spire conical, depressed, short;

   aperture subtrigonal; outer lip thin, angulated near the centre; inner

   lip spread over the surface of the whorls, forming a thickened disc.

   Operculum horny, orbicular, spiral, with numerous whorls.--_Obs._ The

   pretty little shells thus described are found in seas of tropical

   climates. They are distinguished from other genera of the family by

   their lenticular form and the orbicular callosity of the under surface.

   Fig. 357, R. vestiaria.

   RUDISTES. Lam. A family of the order Conchifera Monomyaria, Lam. the

   shells of which are described as irregular, very inequivalve, without

   distinct umbones; the ligament, hinge and animal entirely unknown. The

   shells contained in this family may be thus distinguished.

       the umbones, which form the extremities of the shell. Fig. 194.

       varices. Fig. 198.

       Birostrites is proved to be the cast of a Sphærulites. Fig. 193,

       196.

       200.

   RUDISTES. Bl. The second order of the class Acephalophora, Bl.

   containing the genera Sphærulites, Crania, Hippurites, Radiolites,

   Birostrites and Calceola.

   RUDOLPHUS. Lam. MONOCEROS, Auct.

   RUFOUS. Reddish brown.

   RUGOSE. Rough, rugged.

   RUPELLARIA. Fl. de Belvue. An unfigured shell placed by De Blainville

   in a division of the genus Venerirupis.

   RUPICOLA. Fl. de Belvue. A shell described by De Blainville as an

   equivalve, terebrating species of ANATINA. A. rupicola, Lam.

   SABINEA. A genus of shells resembling small species of LITTORINA, as L.

   Ulvæ, &c. of our shores.

   SADDLE OYSTER. PLACUNA Sella, so called on account of a resemblance in

   shape to a saddle; the part near the umbones being flat, and the

   ventral margins being turned up in a sort of fluting or peak.

   SAGITTA. (_An arrow._) An ancient name for Belemnites.

   SALIENT. (_Saliens._) Jutting out, prominent.

   SALPACEA. Bl. The second family of the order Heterobranchiata, Bl.

   containing no genera of shells.

   SANDALINA. Schum. CREPIDULINA, Lam. A genus of microscopic

   Foraminifera.

   SANGUINOLARIA. Lam. (_Sanguis_, blood.) _Fam._ Nymphacea, Lam.

   Pyloridea, Bl.--_Descr._ Equivalve, inequilateral, transverse,

   sub-ovate, rounded anteriorly, sub-rostrate posteriorly, compressed,

   thin, covered with a shining epidermis, gaping at the sides; hinge with

   two cardinal teeth in each valve, and an external ligament supported

   upon a prominent fulcrum; muscular impressions two in each valve,

   lateral, irregular, palleal impressions with a large sinus.--_Obs._

   This description is made to exclude some of Lamarck's species of

   Sanguinolaria, such as S. occidens, S. rugosa, which are Psammobiæ; and

   to include others which he has left out. The Sanguinolariæ are

   sub-rostrated posteriorly, while the Psammobiæ are sub-quadrate and

   have a posterior angle. Fig. 98, S. rosea. Sandy shores of tropical

   climates.

   SARACENARIA. Defr. A genus of microscopic Foraminifera.

   SAVIGNIUM. Leach. A genus of Sessile Cirripedes, described as composed

   of four valves soldered together, and a convex bivalve operculum; the

   ventral and posterior valve on each side being soldered together, in

   other respects resembling PYRGOMA. Fig. 30.

   SAXICAVA. Fl. de Belvue. Journ. de Ph. an. 10. (_Saxum_, a stone;

   _cava_, a hollow.) _Fam._ Lithophagidæ, Lam. Pyloridea, Bl.--_Descr._

   Transverse, irregular, generally oblong, inequilateral, sub-equivalve,

   gaping anteriorly; ligament external; muscular impressions two,

   lateral; palleal impression interrupted, not sinuated; hinge, when

   young with sometimes two or three minute, obtuse, generally indistinct,

   cardinal teeth; which become obsolete when full grown.--_Obs._ Several

   genera have been founded only upon the difference between the young and

   old shell of the same species of this genus. The Saxicavæ are found in

   the little hollows of rocks; in cavities on the backs of oysters, of

   roots of sea-weeds, &c. in northern and temperate climates. S. rugosa,

   fig. 94.

   SCABRICULA. Sw. A sub-genus of Mitræ, consisting of species which have

   a roughened external surface, &c. Sw. Malac. p. 319.

   SCABROUS. Rough.

   SCALA. Klein. SCALARIA, Auct.

   SCALARIA. Auct. _Fam._ Scalariana, Lam. Cricostomata, Bl.--_Descr._

   Turrited, oval or oblong; spire long, composed of rounded, sometimes

   separate whorls, surrounded by regular concentric ribs; aperture oval,

   peristome reflected continuous, entire.--_Obs._ The typical species of

   this genus, commonly called the Wentletrap, (S. pretiosa) is celebrated

   for the beautiful appearance caused by the numerous ribs encircling the

   whorls, and formerly produced an immense price in the market. It is

   brought from China. There are many smaller species, some of which are

   equally elegant. Fig. 351, S.