Go to National Library of New Zealand Te Puna Mātauranga o Aotearoa
Volume 55, 1924
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Rough Key to Genera and Subgenera.

  • 1. Natica: Globose; sutures generally abutting, but sometimes tangential; parietal callus thin, separated from a prominent funicle in the umbilicus; operculum shelly.

    • (a.) (Carinacca): Ovate; sutures tangential; umbilicus widely open, bounded by a limb without an accompanying sulcus; funicle rudimentary; parietal callus short but fairly thick.

    • (b.) (Magnatica): Large, globose; sutures tangential; umbilicus open, with a weak ridge on apertural wall, also a weak circum-umbilical limb

  • 2. Sulconacca: Small, globose; sutures channelled; umbilicus open, bounded by a low ridge with a well-marked sulcus outside it; no funicle; parietal callus only a thin glaze.

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  • 4. Uber: Ovate; sutures generally tangential; umbilicus open or closed by the parietal callus, which is thick and coalescing with the funicle; operculum horny.

    • (a.) (Euspira): Globose - ovate; sutures abutting, sometimes appressed; apertural callus moderate; no funicle; operculum horny.

    • (b.) (Neverita): Ovate; sutures tangential, appressed; apertural callus thick, coalescing with a huge funicle, which fills the umbilicus; aperture greatly inclined.

  • 4. Sinum: Auriform, extremely flattened, with strong spiral sculpture; aperture distended; columella without callus, concave.

    • (a.) (Eunaticina): Oval; body-whorl compressed, strong spiral sculpture; aperture distended; columella without callus, slightly sinuous.

  • 5. Globisinum. Globose; strong spiral sculpture; inner apertural margin without callus and shaped as a shallow reversed S.

  • 6. Amauropsella: Shell ovate; spire raised; aperture slightly effuse below; umbilicus with a sharp spiral ridge descending to the anterior end of the inner lip; parietal callus thin.

1. Genus Natica Scopoli, 1777.

Shell globose, solid, smooth, suture well marked and generally abutting, aperture semilunar, outer lip straight, often retracted to suture, inclined 20°-30° from vertical, inner margin with moderate callus on parietal wall generally not invading umbilicus which is open and contains a funicle spiralling up apertural wall.

Type: N. vitellus Linné.

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