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经过最近十多年来的工作,在我国早第三纪地层中,发现了许多特有的陆生蜗牛 (Land snalis)化石。这些化石的壳口内部往往具有十分复杂的口栅(Aperture Barriers), 它们对鉴定及分类起着关键性的作用。由于大部分蜗牛化石的口栅位于离口缘较深的部
After more than a decade of work, many unique Land snalis fossils have been found in the Early Tertiary strata of our country. The interior of these fossils often have very complex Aperture Barriers, which play a key role in identification and classification. Since most snail fossils are located in the deeper part of the mouth margin