marine or freshwater mollusks having a soft body with platelike gills enclosed within two shells hinged together
双语例句
The fauna in the Joli Fou consists of bivalves and arenaceous forams. 乔里富组内的化石主要是双壳类和砂壳有孔虫。
Jurassic marine bivalve is very rich, non-marine bivalves also developed rapidly, and their continental formation on the division and correlation played an important role. 侏罗纪的海相双壳类很丰富，非海相双壳类也迅速发展起来，它们在陆相地层的划分与对比上起了重要作用。
