Shelled, amoeba-like organism NAME:
Although most attention in today's world focuses on dinosaurs and why they became extinct, the world of paleontology includes many other interesting organisms which tell us about Earth's past history.
Arrange them from oldest to youngest with the oldest layer on the bottom and the youngest on top.
Many were large a few rare species were 5 feet in length ; crawling and swimming forms; extinct NAME:
Description: The study and comparison of exposed rock layers or strata in various parts of the earth led scientists in the early 19th century to propose that the rock layers could be correlated from place to place. Multibranched relative of starfish; lives attached to the ocean bottom; some living species "sea lilies".