“腹足纲”用英语怎么说？

大多数海洋腹足纲软体动物在某些幼体阶段形成一种有纤毛的游泳器官。Most marine gastropod mollusks develop a ciliate swimming organ in certain larval stages.其中,双神经纲3种,瓣鳃纲68种,腹足纲80种.Among them there are 3 species of Amphineura, 68 species of Lamellibranchi...