A Manual of Conchology / According to the System Laid Down by Lamarck, with the Late Improvements by De Blainville. Exemplified and Arranged for the Use of Students.

by Thomas Wyatt

P. unicolor.

P. impura.

P. muriatica.

P. viridis.

P. vivipara. The viviparous Paludina. Pl. [21], fig. 1.

Thin, ovate, ventricose, wrinkled longitudinally; body with three brown bands: covered with a greenish epidermis; aperture almost round.

3. Ampullaria. Eleven species.

This genus is evidently intermediary to the Paludina and the Natica. Its species are probably all fluviatile; some attain a great size.

Shell thin, globular, ventricose; umbilicus small, forming a compressed funnel-shaped aperture, without interior callosity; spire very short, the last whorl much larger than all the others together; aperture ovate, longer than broad, with margins united; right margin smooth and sharp; columellar lip thickened, projecting, and reflected over the umbilicus; operculum horny, rarely calcareous, thin, oval, not spiral, with concentric elements; summit sub-marginal, inferior, passing obliquely by the right edge of the aperture, but attached to the left.

Ampullaria Guyanensis.