Box 1, Folder 3: Lapham's Collections

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shorter than the tentacula; foot simple

O. Orbiculata Shell subglobular; spire not prominent, but more than convex; whorls 5, obsoletely striated aross, regularly rounded, colour pale, greenish, yellowish, or slightly tinted with yellowish redish [reddish], particularly on the body, & margined above by an obsolete white line, on the middle of the body a white vitta revolves, sometimes ob= scure or wanting, aperture acute above, reg= ularly rounded at the base, & extending from the centre of revoution or base of the column to an equidistance between the base and apex of the spire; base of the columella slightly projecting into an obtuse angle; exterior lip whitish reflected. Length 1/5 of an inch.

Inhabits E. Florida

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(Jour. A.N.S. vol. 1 p283)

Animal pale; rostrum & tentacula blackish, the latter with a white line; eyes very black, elevated in front of a short tubercule; leangth [length] about equal to the breadth of the shell; foot not broader than the body; tail rounded or some= what acute; operculum simple, not spiral yellowish brown, minutely gran= ulated.

This species was found in great numbers on what are called Oystershell Hammocks, near of the river St. John, E. Florida in company with Polygyra septem= volva. When in motion the tentacula are elevated and depressed alternately, as if feeling the way.

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This shell is certainly a Linnaean Helix, but according to the improvements which have been made in Conchology, since the time of the Swedish naturalist, by Mr Lamarck, and other systematists, it is at once excluded from that genus and its congeners, by having but two tentacula, and by its operculated aperture; with the genus Cyclostoma, as it now stands, our shell has more affinity than it has to any other, but a very distinct generic cha= racter is observable in the aperture, which is not orbicular as in the Cyclostoma, but is almost semi-orbicular, greater in leangth [length] than in breadth, and the lips widely dis= united. In addition to the characters usually given of the animal of Cyclostoma, Mr Cuvier remarks that the tentacula are terminated by

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obtuse tubercules; no such appendages are annexed to the cor^responding members of this animal. Upon these considerations, I have thought to construct the present genus

Genus Planorbis

P Glabratus. Shell sinistral; whorls about 5 glabrous, or obsoletely rugose, polished, destitute of any appearance of ca= rina, spire perfectly regular, a little con= cave; umbilicus large, regularly and deeply concave, exibiting [exhibiting] all the volutions to the summit; aperture dclining, remark= ably oblique with respect to the trans= verse diamater. Breadth 9/10 of an inch (Jour. Acad. Nat. Sciences Vol. 1. p280.) [Right Page] 19

Inhabits S. Carolina

Presented to the Academy by Mr L' Hermenier of Charlston, an inteligent [intelligent] & zealous naturalist; he assures me that this species inhabits near Charlston. —

It somewhat resembles large specimens of the P. trivolvis, but differs in the total absence of carina, and in havoing smooth and polished surface, as well as a declining & more oblique aperture, and a more profound and much more regularly concave umbilicus.

[illegible]