OCR Text |
Show 358 MOLLUSCA. has two long tentacula, and the eyes placed ?n pcd~clcs at their external base; the sides of the fool are provided wlth membranous w·m gs, some times simple, at others fringed, and occasionally fur · nishcd with one or two filaments. It is to some of these that belong those petrous and thick opercula observed in cabinets, which were fot·merly employed in medicine under the name of Unguis odoratus. Some of them,-MELEAGER, Montf.(l) are umbilicated, and others,-TuRBO, Montf.(2), are not. DELPHINULA, Lam. The shell thick, as in Turbo, but convoluted in nearly the same plane; the aperture completely formed by the last whorl, anu the ma1·gin not tumid; the animal similar to that of a Turbo. The most common species, Turbo clelphintts, L.; List., 608, 45, takes its name from the ramous and convoluted spines, which have caused it to be compared to a dried fish(3). PLEUROTOMA, Defr. Fossil shells with a round aperture, on the external margin of which is a narrow incision which ascends considerably; it is proba· ble that it corresponded, like that of the Siliquari~, to some cleft in the branchial part of the mantle. M. Deshayes already makes upwards of twenty fossil species. The SoxssuRELLlE of M .. d'Orbigny are living species of the same. TuRRITELLA, Lam. The same round aperture as in Turbo properly so called, and (1) Turbo pica, L. List., 640, 30;-T. m•gyrostomus, Chemn., V, clnvii, 1758-61 ;-T. margaritaceus, lb., 1762;-T. versicolor, List., 576, 29;-T. mespi· lus, Chemn., V, clxxvi, 1742-43;-T. granulatus, lb., 44-46;-T. ludus,lb., 48, 49;-T. diadema, ld., p. 14-5;-T. cinereus, Born., XII, 25, 26;-T. torquatus, Chemn., X, p.' 295;-T. undulatus, lb., clxix, 1640-41. (2) Turbo petlwlatus, List., 584·, 39;-T. cocltlus, lb., 40;-T. chrysostamuJ, Chemn., V, clxxviii, 1766;-T. rugosus, List., 647, 41;-T. marm01'atus,Id., 587, 46;-T. sarmaticus, Chemn., V, clxxix, 1777-18, 1781;-'Z'. cornutus, lb., 1779- 80;-T. olearius, ld., elxxviii, 1771, 72;-T. radiatus, Id., clxxx, 1788-89; -T. imperialis, lb., 1790;-T. coronatus, lb., 1791-93;-T. canaliculatus, Id., clxxxi, 1794;-1'. setosus, lb., 95-96;-T. spinosus, lb., 1797;-T. sparveritu, lb., 1798;-T. Moltkianus, lb., 99-1800;-1~ Spenglcrianus, lb., 11:!01-2;--T. castanea, Id., clxxxii, 1807, 1814;-T. crenulatus, lb., 1811-12;-T. smarag· dulus, lb., 1815-16;-T. cidaris, Chemn., V, clxxxiv;-T. ltelicinus, Born., XII, 23-24. (3) Add; Turbo nodulosus, Chemn., V, elxxiv, 17:.:!3-24;-T. carinatus, Born., XIII, 3-4;-.Brgonauta, cornu, Fichtel and Moll., Test. Micros., I, a, e, 01 ' LIP' PISTE, Montf. GASTEROPODA PECTINIBRANCHlATA. 359 completed, also, by the penultimate whorl; but the shell is thin, and is so far ft•om being convoluted in one plane, that its spire is prolonged into a turreted obelisk. The eyes of the animal are placed on the external base of its tentacula; the foot is small( 1 ). They are found in great numbers among fossils; the PRoTo, Defr., should be approximated to them. SoALARIA, Lam. The spire, as in Turritella, elongated into a point, and the aperture, as in Delphinula, completely formed by the last whorl; it is moreover surrounded by a ridge, which is formed from space to space as the shell of the animal increases in size, resembling so many steps. The tentacula and penis of the animal are long and slender. One species celebrated for the high pt·ice it commands(2), the Turbo scalaris, L.; Chemn., IV, clii, 1426, &c. vulg. Sealata, is distinguished by the whorls only coming in contact at the points where the ribs unite them, the intervals being open. A second species, the Turbo clathrus, L.; List., 588, 50, 5lt is not marked by this peculiarity; it is more slender, and very ·common in the Mediterranean. Some terrestrial or fresh water subgenera, in which the aperture is entire, round, or nearly so, and operculated, may be placed here. Of this number is the CYcLOSTOMA, Lam.(3) 'l'he Cyclostomre should be distinguished from all the others because they are terrestrial, as instead of branchi~, the animal has merely a vascular network spread over the parietes of its pectoral cavity. In every other respect, however, it resembles the other animals of this family; the respiratory apertu1·e is formed in the (1) Turbo imbricatus, Martini, IV, clii, 1422;-T. replicatus, lb., eli, 1412; List., 590, 55;-T. acutangulus, List., 591, 59;-T. dttplicatus, Martini, IV, eli, 1414;T. exoletu11, List., 591, 58;-T. te1'ebra, Icl., 590, 54;-T. variegatus, Martini, IV, clii, 1423;-T. obsoletus, Born., XIIJ, 7. (2) Enormous sums have been paid for this shell, which is the Wentletrap of collectors and dealers. One in llullock's Museum, London, was valued at two ltundred guineas, and four specimens, at one sale, brought from sixteen to twenty oc~d pounds sterling each. The price now is reduced, but a decent specimen is strll worth. several guineas. .Om. Ed. (3) The Cyclostomre and the Helicines form the order of the PuLMONEA OPEncu• LATJ. of M. de Ferussac. |