An illustrated introduction to Lamarck's conchology; contained in his Histoire naturelle des animaux sans vertèbres: being a literal translation of the descriptions of the recent and fossil genera / Accompanied by ... plates. By Edmund A. Crouch, F.L.S.

  • Edmund A. Crouch
Date:
1826
Catalogue details

Licence: Public Domain Mark

Credit: An illustrated introduction to Lamarck's conchology; contained in his Histoire naturelle des animaux sans vertèbres: being a literal translation of the descriptions of the recent and fossil genera / Accompanied by ... plates. By Edmund A. Crouch, F.L.S. Source: Wellcome Collection.

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    SECTION III. Either no ligament, or none known; or represented by a tendinous cord, which supports the shell. This Section contains Two Families—Rudista, and Brachiopoda. RUDISTA. — 6 Genera. Ligament, hinge, and animal unknown; shell very inequivalve. No distinct beaks. Sph^erulites.—Shell inequivalve, orbicular-globose, rather depressed above, echinated externally with large, subangular, horizontal scales; upper valve smallest, rather flat, opercular; the internal surface furnished with two unequal, subconical, curv¬ ed, and prominent tuberosities; lower valve largest, rather ventricose, the exter¬ nal margin radiated with scales; cavity obliquely conical, and forming on one side, by the folding of the internal margin, a crest, or projecting keel: internal side of the cavity transversely striated. Hinge unknown. Plate XXI. Fig. 6. S. foliacea. Fossil. [Icon.—Encyc. Method, pi. 172. fig. 70 Radiolites.—Shell inequivalve, externally striated; the striae longitudinal, radiating: lower valve turbinated, and largest; the upper, convex or depressed conical, oper¬ cular. Hinge unknown. Plate XXI. Fig. 7* R. turbinata. [British Museum.] Calceola.—Shell inequivalve, triangular, turbinated, flattened beneath; the larger valve hollowed or hood-shaped, obliquely truncated at the aperture; the cardinal mar¬ gin straight, transverse, a small notch or indentation in the middle; the superior margin arched: the small valve flat, semi-orbicular, opercular, having a tubercle on each side of the cardinal margin, and, in the middle, a pit with a small lamina. Plate XXI. Fig. 8. C. sandalina. [Mr. J. D- C. Sowerby’s Cabinet.] Birostrites.—Shell inequivalve, bicornute, the disk of the valves elevated conically, un¬ equal, obliquely diverging, nearly straight, horn-shaped, the one enveloping the other at the base. Plate XXI. Fig. 9. B. insequiloba. [Mr. J. D. C. Sowerby’s Cabinet.] Discina.—Shell inequivalve, oval-rotundate, rather depressed, valves nearly equal, each having an orbicular disk in the centre, very distinct; disk in the upper valve not perforated, with a mammillated protuberance in the middle; that in the other valve very white, divided by a small transverse slit. Plate XIII. Fig. 2. D. Norvegica. (Orbicula Norvegica.—Sowerby’s Genera.) [Mr. G. B. Sower- (a) Lower valve of ditto. by’s Cabinet.] (b) Upper valve of ditto. Crania.—Shell inequivalve, suborbicular, lower valve almost flat, perforated in the in¬ ternal surface by three unequal and oblique holes; the upper valve very convex, furnished interiorly with two prominent callosities. Plate XIII. Fig. 3. C. personata. (Anomia craniolaris.—Linn.) (a) Lower valve of ditto. (b) Upper valve of ditto,