260 W. Lilljeborg on the Genera Peltogaster and Liriope. Corbicula Quilonica, B. Testa insequilaterali, trigono-rhomboidea, gibba, tenui, concentrice subremote costata, costis postice evanescentibus, sulcis intermediis latioribus, sub lente decussatim striatis, albida vel lutea, radiis fuscis angustis ornata ; umbonibus prominentibus, apice fere eroso ; latere antico breviore, valde arcuato, angustiore, postico striato, latiore ; superne et basin versus angulata ; margine ventrali me-diocriter arcuato ; ligamento oblongo intra nates attenuato ; pa-gina interna valde concava, albida, maculis radiisque purpureis ornata ; dente mediana valvae dextrse duplici, dentibus lateralibus brevibus serrulatis. Lat. 10, long. 8, crass. 5£ mill. Habitat prope Quilon in stagno cum Clea Annesleyi. The younger shells are more gibbous towards the umbones in proportion to their length than the larger specimens. A tawny-yellow epidermis covers the fresher specimens. The rays are numerous, more or less broad, sometimes appearing as mere lines of small spots, and occasionally spreading so as to make the surface appear nearly black. The species is very distinct from any of the Corbicula collected by myself or obtained from Northern or Central India. The shortness of the lateral teeth, on the anterior side especially, is a notable character, as well as the insequilateral form, which is more conspicuous in the young than in the adult shell. Dursley, August 29, I860. Note. — The water contained in the tank which is inhabited by Clea Annesleyi and Corbicula Quilonica is probably brackish. A parcel, received while this paper was passing through the press, includes specimens of a Cerithium resembling C. eximium, Sow., obtained from the same pond, which has a muddy bottom and grassy banks perforated by a small crab. In a large speci-men of Clea, 10 mill, in length by 5^ in breadth, with five whorls and a less eroded apex, the last whorl scarcely attains ^ of the total length of the shell. September 3, 1860. XXXIV. — On the Genera Peltogaster and Liriope of Rathke. By W. Lilljeborg. [With a Plate.] [Continued from p. 173.] Liriope pygmcea, Rathke. Beitrage zur Fauna Norwegens, Nova Acta Acad. Leop. 1843, vol. xx. p. 60, tab. 1. figs. 8-12. Sine dubio mas junior, tarn en non ineunte aetate. On the 23rd of July, 1858, the author found in the sea, near