| This study concerns all infaunal brachiopods that possess an inarticulate, organo-phosphatic, linguliform shell. |
| Lingulids are shallow burrowing infaunal filter feeders of the shallow intertidal zone. |
| Results from a pair of epifaunal and infaunal dendrochirotids from Family Cucumariidae indicate little variation in the relative amount of ossification. |
| If so, the oldest traces of locomotory activities of the metazoans should be connected with their infaunal life. |
| Within a particular paleoenvironment the organisms could further subdivide resources by establishing epifaunal, and possibly infaunal, tiers. |
| The remaining five deposit-feeding bivalves are infaunal burrowers. |
