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Zoological Illustrations Series II/Plate 91

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Zoological Illustrations Series II
William Swainson
Ser. 2. Vol II. Pl. 91. Geotrochus pileus.
1560724Zoological Illustrations Series II — Ser. 2. Vol II. Pl. 91. Geotrochus pileus.William Swainson

GEOTROCHUS pileus.
Cap Land-Trochus.

Plate 91.
Plate 91.


GEOTROCHUS pileus.

Cap-shaped Land-trochus.

Order Phytophages. Swains. Tribe ——

Sub-Generic Character.

Shell pyramidical, each volution, reckoning from the base, gradually diminishing and forming a conic spire, basal volution depressed, margin of the outer lip reflected and entire.




Specific Character.

Shell trochiform, smooth, generally banded with reddish and yellowish bands: volutious convex.

Trochus Pileus. Chemnetz. Pl. 122. f. 1046-7-8.

Helix pileus. Dillwyn. p. 933. No. 106.

Lister. Tab. 14. f. 11.

In Mus. Nost.

Although this shell, in artificial arrangements, may be very well placed among the sub-divisions of Helix or Bulimus, we feel persuaded that it is, naturally, the type of a Sub-genus: we have no hesitation, therefore, in recording it as such. Another species, sharply carinated, semi-transparent, and of a milky whiteness, we discovered in Brazil: and we are thus led to conclude that the habitat of Geotrochus pileus, which no author has yet mentioned, may probably be Tropical America.

The figures of this species, given by Chemnitz and Born, represent it as marked by several narrow bands of a rufous brown colour: but the variety here delineated, has only one, of a deep purple; it is almost the only specimen answering to this description, which we have yet seen: both varieties are very rare, and much prized by collectors.