LIMNEA. Lam. ([Greek: Limnas], _limnas_, lacustrine.) _Fam._ Limnacea, Lam. and Bl.--_Descr._ Oblong, light, thin; spire variable in length, acute; last whorl large, aperture large, longitudinal, entire; inner lip spread over a portion of the last whorl; columella forming an oblique fold; outer lip rounded at each extremity, thin.--_Obs._ These light horn-coloured shells are common in standing pools, ponds and ditches, in various parts of Europe. They resemble the Amber shell (Succinea) in shape, but the animal of the latter is amphibious, and the shell of a bright amber colour. L. Stagnalis, fig. 308. L. auricularia, fig. 309. (RADIX, Montf.) The reversed species have been separated under the name Physa, fig. 310. Other generic names have been given to other species. LINES OF GROWTH. The concentric striæ or lines formed by the edges of the successive layers of shelly matter deposited by the animal by which it increases the shell. The outer edge of the aperture is always the last line of growth. LINGUIFORM. (_Lingua_, tongue; _forma_, form.) Tongue-shaped. LINGULA. Lam. (Dim. from _lingua_, tongue.) _Fam._ Brachiopoda, Lam. Palliobranchiata, Bl.--_Descr._ Equivalve, oblong, depressed, thin, equilateral, gaping and pointed at the umbones, gaping and truncate or trilobate at the opposite extremities, attached by a fleshy pedicule fixed to the umbones.--_Obs._ This is the only bivalve shell which is pedunculated, in which respect it constitutes a singular anomaly. The ancient writers, seeing the valves separate, placed it in their systems under the name Patella Unguis. There are several recent species found in the Moluccas, and some fossils in sandy indurated marl, and in alluvium of Suffolk. L. Anatina, fig. 219, is so named from its resemblance to a duck's bill. LINGULINA. D'Orb. A genus of microscopic Foraminifera. LINTHURIS. Montf. Conch. Syst. 2. 154. A genus of microscopic Foraminifera. LIP. See LABIUM and LABRUM. LIPPISTES. Montf. A genus of microscopic Foraminifera.