Notes on some Fossil non-Marine Mollusca and a Bivalved Crustacean ( Estheriella ) from Nyasaland

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Abstract
T he specimens described in these notes have been collected by Messrs. A. R. Andrew & T. E. G. Bailey in the north-western area of Nyasaland, during a mineral survey carried out between the years 1906 and 1908, under the auspices of the Imperial Institute, the authorities of which have kindly presented them to the Geological Department of the British Museum (Natural History). They consist of Quaternary gastropoda and Palæozoic pelecypoda, accompanied by Estheriella , all of which exhibit non-marine characters. Quaternary Gastropoda The Quaternary gastropoda include both freshwater and terrestrial forms belonging to the recent fauna of Lake Nyasa and its surrounding shores. Generally speaking, these specimens are of fresh appearance and well preserved, frequently showing remnants of coloration and periostracum—a condition which more particularly applies to the land-shells. The freshwater shells comprise the genera Viviparus and Lanistes , the former having been obtained from deposits at Chiwondo on Lake Nyasa, at an elevation of 20 feet above the water-level, as well as 3 miles west of that village at the altitude of 350 feet above the same level, where they occur as marl-casts, and again at Chisali, 15 miles west of the lake, at an elevation of 400 feet, where their casts form a limestone of sóme durability. Examples of Lanistes were collected at Chiwondo from a height of 20 feet, in association with well-preserved Viviparus . The terrestrial shells are localized from Chiwondo and Masiunjuti, the latter place being situated some 12 miles west of the lakemargin, where the specimens were