TURBINID.E.] 



MUSEUM OF ANIMATED NATURE. 



211 



of the Isle of Wight and from the Oxford oolite in 

 Dorsetshire, and another uncertain species from the 

 last-named locality. See this list also for localities 

 of Pieurotomaiia. (' Strata between the Chalk and 

 Oxford Oolite.) 



Nor is it wanting in the Silurian rocks, where Mr. 

 Murchison records the presence of the genus in the 

 old red sandstone (middle and lower beds only), in 

 the upper Ludlow rock, and (with a ?) in the Cara- 

 doc sandstone. In the same elaborate work Pleu- 

 rotomaria is noted from the lower Ludlow rock and 

 from the Caradoc sandstone. ('Silurian System.") 



Solarium. — M. de Blainville observes that 

 Lamarck records eight fossil species, and Defrance 

 seventeen, some of which are subanalogues from 

 the calcaire grossier. M. de Blainville also notes 

 the fossil Solarium magnum (Maclurite from North 

 America, and adds that Defrance enumerates eight 

 species of Euomphalus (fossil). 



Mr. G. B. Sowerby observes that a few fossil spe- 

 cies occur in the tertiary beds ; and that there are 

 some fossils belonging to the lower beds of oolitic 

 formation, and even as low as the mountain lime- 

 stone, which resemble them very nearly: these, he 

 adds, form the genus Cirrus of some authors, and 

 do not appear to him to possess any characters by 

 which they may be generically distinguished from 

 the Trochi, Turbines, or Solaria. 



M. Deshayes, in his tables, makes sixteen the 

 number of fossil Solaria (tertiary), and names So- 

 laria variegatum, carocollatum, and pseudo-perspec- 

 tivum as species found both living and fossil (ter- 

 tiary). 



In the list of Red Sea shells above referred to So- 

 larium perspectivum appears. 



That the genus occurs below the chalk is evident 

 from Dr. Fitton's List, also above referred to, where 

 three species are recorded from the upper green- 

 sand, the gault, and Blackdown. Cirrus is also 

 noted from the upper green-sand of Dorset. 



Solarium does not appear amongst the fossils of 

 the Silurian rocks, but no less than nine species of 

 Euomphalus are recorded in Mr. Murchison's tables, 

 coming respectively from the Aymestry limestone, 

 the Lower Ludlow rock, the Wenlock limestone, the 

 Wenlock shale, the Caradoc sandstone, and the 

 Llandeilo flags. 



These works are only quoted as examples out of 

 many fossil lists which should be examined by the 

 student. 



Here may be best noticed the Rotella mana (from 

 the Claiborne beds, Alabama, tertiary) of Mr. Lea, 

 who observes that he is not aware that the genus 

 Rotella has before been observed in a fossil state 

 in America or in Europe, and refers to the tables of 

 M. Deshayes, who gives four recent species, but 

 none fossil. (' Contributions to Geology.') 



Family TURBINID^E. 



In this family, according to Cuvier, are compre- 

 hended all the species with the shell completely 

 and regularly turbinated, and with the mouth en- 

 tirely circular. The subdivisions or subfamilies are 

 numerous. 



The species included in the genus Turbo, Les 

 Sabots of the French, are described by the same 

 author as having the shell round or oval, thick, and 

 with the mouth completely on the side of the spire 

 by the penultimate whorl. The mollusk has two 

 long tentacles, with the eyes carried on peduncles 

 at their external base ; on the sides of the foot 

 there are membranous wings or expansions, which 

 are sometimes simple, sometimes fringed, sometimes 

 furnished with one or two filaments. It is to some 

 of these species that those thick, solid, calcareous 

 opercula belong, which are remarkable in collec- 

 tions, and which were formerly employed in medi- 

 cine under the name of Unguis adoratus. Some 

 species, he adds, are umbilicated (Meleagris, Montf ), 

 and others not umbilicated (Turbo, Montf.). 



M. de Blainville, in reference to the Turbinidae 

 (genus Turbo of Linnaeus), gives the following gene- 

 ral characters : — 



Animal slightly variable, rather, however, with 

 reference to the form and proportion of certain ex- 

 ternal parts than to the totality of its organization, 

 and bearing a great resemblance to that of a Tro- 

 chus. 



Shell equally variable in its general form, but 

 with the aperture always nearly circular and com- 

 pletely closed by a calcareous or horny operculum ; 

 the spiral whorls are few, and the apex is sub- 

 lateral. M. de Blainville in further observations 

 remarks, that in reality there is very little distinction 

 between this family and the Trochidse, and that, in 

 fact, the Linnaean jenus Trochus is fused by in- 

 sensible gradations into the Linnsean genus Turbo; 

 and he adds, that it is only with a view of making 

 the conchological system of Linnajus accord with 

 that of modern authors that he has established the 

 present family. 



With respect to the habits and manners of the 

 Turbinidse, it would appear that they frequent sub- 

 Vol. II. 



marine banks covered with sea-weeds, and are all 

 phytophagous, or vegetable feeders ; a few are 

 natives ol fresh waters, and a limited number respire 

 air. With respect to the restricted genus Turbo of 

 modern naturalists, M. de Blainville thus charac- 

 terizes it ; — 



Animal nearly resembling that of the Trochi ; the 

 sides of the body are frequently ornamented with 

 tentacular appendages vaiying in form and number. 

 The head is prolonged into a proboscis ; the ten- 

 tacles are slender and setaceous ; the eyes often 

 subpedunculate ; the mouth is without a labial 

 tooth, but provided with a very long lingual riband 

 rolled spirally and contained in the abdominal 

 cavity ; there is a transverse furrow at the anterior 

 border of the foot ; two branchial pectinations ; 

 shell thick, nacreous, internally depressed, conical 

 or subturriculate, sometimes umbilicated, and some- 

 times slightly carinated on its circumference ; 

 aperture circular or slightly depressed ; the oper- 

 culum is calcareous or horny, and in the latter case 

 the .spire is visible on the outer side, but in the 

 calcareous opercula the spire is visible on the 

 internal side. M. de Blainville divides the genus 

 Turbo into ten sections for the sake of convenience. 

 With regard to the internal anatomy of the 

 mollusks of the genus Turbo, MM. Quoy and 

 Gaimard have entered fully into details, which it 

 would be here out of place to follow. See the 

 atlas of the Astrolabe (Zoologie, pi. 59, f. 10). 



2684.— The Marbled Turbo 



(Turbo marmoratus). This large and beautiful 

 shell is well known to conchologists, and is a native 

 of the Indian seas. Living specimens were brought 

 to the Astrolabe at Aboyna, by the Malays, but 

 MM. Quoy and Gaimard were unable to obtain any 

 account of the habits of the animal. It would 

 appear that the mollusk is used as food by the 

 natives of Wagiou, and those voyagers often found 

 the empty shells of this turbo upon the heaps of 

 other molluscous shells from which the inhabitants 

 derive a great portion of their subsistence. 



The shell is subovate, very ventricose, imperforate, 

 smooth, of a green colour, marbled or subfasciated 

 with green and white ; the last whorl is transversely 

 nodulous in a triple series, the upper nodules the 

 largest ; the lip at the base is flattened into a short 

 subreflected process : the mouth silvery. This 

 shell, when deprived of its external layer, exhibits a 

 silvery, iridescent, and very beautiful nacre. The 

 operculum is white externally, chestnut infernally. 



Referring to Fig. 2684, a represents a back view 

 of the shell ; b, a view of the shell, presenting the 

 mouth, with the operculum in situ; c, the inside of 

 the operculum. 



26a5.— The Twisted Turbo 



{Turbo torquatus). This is a large shell, orbiculate- 

 convex, broadly and deeply umbilicated, transversely 

 sulcated, substriated with close-set longitudinal 

 lamella, of a green grey colour. The spire is blunt 

 at the apex. The shell when deprived of its first 

 layer is beautifully nacreous. 



According to MM. Quoy and Gaimard the foot 

 of the mollusk often assumes a quadrilateral form, 

 but it can elongate itself into a trumpet shape. It 

 is yellow below, dotted with reddish brown on the 

 lateral parts. 



This species inhabits King George's Sound, but 

 few living specimens were found by the French 

 voyagers. 



Referring to Fig. 2685, a represents the shell 

 with the animal seen from below, the foot assuming 

 a quadrilateral form; 6, the animal removed from 

 the shell, with the foot trumpet-shaped ; c, the 

 outside of the operculum ; d, the inside of the 

 same. 



2686.— Cook's Turbo 



{Turbo Cookii). The general form, ridges, imbri- 

 cations, and markings of this beautiful shell are so 

 well expressed by the tigures, as to relieve us from 

 the necessity of entering into a minute description, 

 rather perplexing from the terms employed by 

 conchologists than conveying clear and precise 

 ideas to the general reader. It is in fact not very 

 easy to express in words the details of a shell, 

 though the eye at once seizes them ; nor do the 

 compound words derived from the Latin, as orbicu- 

 late-convex,imbricato- squamous, and the like, serve 

 except for the professed naturalist ; and though we 

 have occa-sionally used such terras, we have at the 

 same time felt that to most they would convey but 

 little information. One of the difficulties indeed 

 under which the naturalist labours in his attempts 

 to describe the form and structure of objects 

 popularly, arises from the circumstance that the 

 terms he uses are either not in common use, being 

 coined as it were to meet the necessities of science, 

 or if used are not so in the sense in which he 

 employs them. In fact the student in zoology and 

 botany has to familiarize himself, as a preliminary 



step, with a list of scientific terms, used in a peculiar 

 sense, which, when once understood, he perceives 

 to be definite and expressive, but which ,constitute 

 as it were a language per se, and to others destitute 

 of meaning. With regard to shells we have greatly 

 felt this difficulty, and the more so as, by way of 

 relief to these dry and perhaps repulsive details, we 

 can say so little of the habits and manners of their 

 mollusks. On the contrary, quadrupeds, birds, 

 reptiles, and fishes, from the variety of their instincts 

 and modes of life, from their activity, their opera- 

 tions, their change of place, and their external 

 structure, diverse for given ends, aftbrd inex- 

 haustible materials for descriptions replete with 

 interest. Yet is the study of shells and their 

 occupants of great importance, signally so indeed 

 to the geologist, who at every step has to determine 

 the affinity of extinct fossil species to those now 

 existing, to trace the gradual approach of forms 

 long passed away, through successive periods, to 

 those now tenanting the waters of our globe ; ana 

 is thereby enabled to amass a fund of materials, 

 giving him the power of determining the diff'erence 

 or agreement of strata in various parts of the globe, 

 and their respective ages. To the anatomist again 

 the molluscous occupants of these external skeletons, 

 as they may be considered, offer a boundless field 

 of investigation, and present him with examples of 

 wonderful and interesting organization. Hence is ' 

 the term Conchology almost abandoned, and the term 

 Malacology {jMiKaxos, soft in allusion to the mol- 

 lusks, and Koyos) generally adopted in its room. 



"The shell-collector of former days," says an 

 eloquent writer, "looked upon his drawers, if they 

 were rich in rare species or varieties, as containing 

 an assemblage of gems ; and indeed the enormous 

 prices given for fine and scarce shells, joined with 

 the surpassing beauty of the objects themselves, 

 almost justified the view which the possessor took 

 of his cabinet of treasures. They were to him 

 really ' Les Delices des Yeux et de I'Esprit ;'* and 

 the energetic zeal with which he collected and the 

 sacrifices that he made to procure a fine and perfect 

 Many-ribbed Harp, a Gloria Maris, or Cedo Nulli, 

 among the cones ; an Aurora or Orange-Cowry, a 

 V'oluta aulica or Voluta Junonia, &c., were only 

 comparable to the extravagances of those visited by 

 the tulip mania when it was at its height. But 

 though they were the delight of his eyes, they were, 

 in nine cases out of ten, little more to the owner of 

 them : they were mere trinkets on which he looked 

 dotingly \vithout knowing, and scarcely wishing to 

 know, the organization of the animal whose skeleton 

 only was before him. This innocent trifling came 

 at last to be viewed in its true light by some 

 collectors worthy of better employment, who put off 

 childish things and went deeper into the subject. 

 Lister, Adanson, Linnaeus, Poll, Cuvier, Lamarck, 

 De Blainville, and others gave dignity to this de- 

 partment of zoology, and gradually raised the 

 science to its proper rank ; whilst the comparatively 

 imperishable nature of the covering of the testaceous 

 mollusks became, in the hands of such men as 

 William Smith and his followers, among the most 

 valuable records by which the stratification of the 

 earth's crust could be demonstrated and its geological 

 history deciphered." 



But we must return from this digression to the 

 species of Turbo before us. 



The Turbo Cookii was found by MM. Quoy and 

 Gaimard in great numbers in Tasman's Bay, New 

 Zealand, in the Bight of the Astrolabe (I'Anse de 

 I'Astrolabe), and on the reefs of the Passe des 

 Frangais. These scientific explorers observe, that 

 we may judge of its small degree of locomotiMi 

 from the dirty incrustation, so difficult to be removed, 

 with which the shell is covered. It grows to a con- 

 siderable size. 



A common form of the Turbidinse with which 

 all are familiar, is the ordinary periwinkle, Le 

 Vogneau of the French (Littorina vulgaris, Foruss.), 

 Turbo littoreus, Linn. This species abounds in 

 rocky places in our seas, and is used as food, but is 

 not very digestible, and has been known to occasion 

 dangerous disorders. According to Pennant the 

 Swedish peasants believe that when these shells 

 creep high up the rocks, they indicate a storm from 

 the south. Linnseus quotes Stroem, the Norwegian, 

 for a different augury ; when it ascends the strand 

 it indicates an approaching land-wind, and a calm 

 in-shore. A species in the hotter seas, Littorina 

 pulchra, has been found on mangrove-trees fourteen 

 feet above the water, and has been kept alive with- 

 out water for six months. Another genus belonging, 

 according to the opinion of MM. Quoy and Gaimard, 

 to the present family, and indeed closely related to 

 Turbo, is Phasianella. 



The shells of the mollusks of this genus, once so 

 rare, began, as these naturalists observe, to be ot 

 less value in consequence of Baudin's voyage ; and 



• The French title of Knorr** ceiebratetl work in German and 

 French. The German title is * Vergnugen der Augen und des 

 Gemutiu,' 4to., Nuremberir, 17S7, 1764. 



2E2 



