90 Mr. W. H. Benson on new Land Shells from Ceylon. determined the whole of them, with the exception of C. Calthce, xanthocq>halum, eryt/u-opus, ohscurum and nigriceps. Heer has a species, C pulchelhim, found in Switzerland, which, from his insufficient description, I have been unable to identify. With the above exceptions I think I have noticed the whole of the European species hitherto known. IX. — Characters of new Land Shells, collected by Edgar L. Lay-ARD, Esq., in Ceylon. By W. H. Benson, Esq. 1. Streptaxis Layardiana, nobis. Testa arcuato-rimata, depresso-ovata, abbreviata, lata, leviter striata, albido-cornea ; spira subelevata, apice planulato, excentrico ; sutura crenulata : anfractibus 5, convexiusculis, ultimo ad latus deviante, basi convexiuscula, Isevi ; apertura straminea, subtriangulari uni-plicata, marginibus callo lamellam intrantein validam emittente jmictis, dextro expanse reflexiusculo, antrorsum arcuate, superne profunda sinuato, columellari et basali reflexis, umbilico intus ru-goso-striato. Diam. major 10§, minor 8, alt. 4 mill. Hab. inter lapides ad verticem rupis Mehintali Insulae Ceylon. In one or two specimens the callus near the upper margin is inclined to form an obtuse tooth at the side of the sinus, which is much deeper than in H. Perrotetiana, Petit, from the Nil-gherries. A graphic account of the discovery is contained in Mr. Lay-ard's Journal in page 235, vol. xi. of the ' Annals.' This and the following curious species, of a singular genus, capriciously distributed through the tropical regions of the globe, are the first which have been found in Ceylon. The head-quarters of the genus are in South America and Western Africa. The remain-ing species, of which the locality is known, are solitary in the Nilgherry Hills of South India, at Tavoy on the Tenasserim coast of the Bay of Bengal, in Cochin China, and in the Sey-chelles and Rodriguez, islands of the Southern Indian Ocean. M. Petit de la Saussaye objects (Journ. de Conchyl. 1851, p. 369) to the reception of Streptaxis as a genus, considering it to be inadmissible in a zoological point of view ; and he adduces as an argument for rejection the circumstance of its gradual change into Helix, through species which belong to the group, . although deficient in the principal character of distortion. The same argument might be used against the reception of most other genera. Bulimiis and Achatina have as little title to sepa-ration as this genus and Helix ; and Streptaxis has equal claims
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