Bryozoan:
Like brachiopods bryozoans are abundant in
Paleozoic limestones and have calcite fibers arranged generally parallel to the
shell wall. The shapes of these allochems however reflect that they
are colonial organisms. Circular to ovoid intraparticle pores (former
living chambers), are evident in many byozoan fragments. If the pieces are
broken into such small bits that you can no longer discern this larger
structure, then they are difficult to discriminate from similarly comminuted
brachipod fragments.