石燕是属于腕足动物门的一类(一个目)无脊椎动物。腕足动物是海生底栖,单体群居,具真体腔,不分节而两侧对称的无脊椎动物。体外披着两瓣大小不等的壳,壳质为钙质或几丁磷灰质。有性生殖,幼虫约有数天至两周的浮游期,其 Shi Yan is a kind of (a head) invertebrate belonging to the Brachiopod door. Brachiopods are marine benthic, single social groups, with the true body cavity, regardless of section and bilateral symmetry of invertebrates. In vitro with two shells of different sizes, chitin or chitin apatite. Sexual reproduction, larvae about a few days to two weeks of flooding, its