17. Know functions as well as structures. Functions of structures detailed in the manual will not always be included in the text. You are still required to know the function.
23. Class Ophiuroidea Brittle star: Early Ordovician, ~500 million years ago Five arms joined to central body disk Organs of digestion and reproduction never enter the arms Arms regenerate
24. Class Echinoidea - sea urchins & sand dollars Apperaed 450 Mya Test is round and spiny No arms
25. Class Holothuroidea - sea cucumbers Elongated body and leathery skin Endoskeleton below the skin
39. Class Actinistia - lobe-finned fishes They were believed to have been extinct since the end of the Cretaceous, until the first specimen was found off the east coast of South Africa, off the Chalumna River in 1938
40. Class Dipnoi - lungfish These fish have lungs Live in arid habitats that experience seasonal droughts