paleozoic paleozoic era ordovician period class crinoidea trilobite
in a rock, shell, or on a rock rock or sedimentary in composition spiny, leathery skin attached to a rock a carapace (top shell) that is divided into three or more parts
the presence of fossils or other artifacts the presence of sedimentary, metamorphic, or igneous rocks spines or ridges on the exoskeleton spiny ridges along its back sandy or rocky ocean floor
a rock with a black background
fossilized the presence of fossils or other artifacts the presence of sedimentary, metamorphic, or igneous rocks grey rock limestone
trilobite which has long antennae trilobite which has short, jointed legs trilobite which has two-lobed tail trilobite which has segmented body fossil which has usually found in sedimentary rock
trilobite which has long antennae trilobite which has short, jointed legs trilobite which has two-lobed tail trilobite which has segmented body trilobite which has compound eyes
trilobite fossil charophyta decapoda ankistrodesmus
trilobite fossil isopod chiton rock
trilobite which has compound eyes trilobite which has shell-like exoskeleton trilobite which has segmented body trilobite which has short, jointed legs trilobite which has two-lobed tail
trilobite which has shell-like exoskeleton trilobite which has short, jointed legs trilobite which has compound eyes trilobite which has two-lobed tail trilobite which has segmented body