1. Type of preservation by which soft tissues may be preserved as a thin film after volatiles (H & O) are driven off in a reducing environment. _________________________________

2. Ecological zone defined by the depth to which light penetrates the marine environment. ___________________________________

3. Larval form shared by several invertebrate phyla, including: annelids, arthropods, molluscs, brachiopods and bryozoans. ________________________________

4. Phosphatic, tooth-like microfossils found throughout the Paleozoic; now thought to be chordates. _________________________________________

5. Asexually-reproducing, sessile form of a coelenterate that undergoes alternation of generations. _________________________________

6. Term that describes a species that will tolerate only a narrow range of salinity conditions in the environment. _____________________________________

7. Lustrous shell substance composed of alternating layers of aragonite and organic material found in some mollusks; mother-of-pearl. __________________________

8. Habit of a graptolite rhabdosome characterized by repeated branching with secondary connections between branchs; thought to be primitive form for the group. ______________

9. "Head" of a crinoid from which the arms arise. ______________________

10. Root-like or massive structure that anchors crinoids (as well as some other sessile organisms) to the sea floor. ____________________________________

11. Term that describes organisms that lack nuclei or other organelles. _______________________________

12. Feeding structure that surrounds the mouth in bryozoans. __________________

13. Support structure attached to the lower valve in most brachiopods that attaches them to the substrate. ________________________________

14. Term for small calcareous or siliceous skeletal elements; used for many groups such as sponges or sea cucumbers. ________________________________

15. . Rasping feeding structure found in most mollusks. __________________________

1. Hinged structure that covers the aperture in cheilostome bryozoans.

a._________________________ b. ___________________________

2. Line that represents the external trace of the intersection of the septum with the outer wall of a cephalopod conch.

3. The skeletal structure that houses an individual graptozoan zooid; arrayed along a stipe.

4. Disc-shaped, calcite plates that extend through the arms of ophiuroids.

5. Processes that occur on the pedicle valve of articulate brachiopods that key into sockets in the brachial valve.

1. interval zone; assemblage zone; abundance zone; stereozone

2. phylogenetic; phenetic; dianetic; classical;

3. ascon; sycon; leucon; cephalon

4. stone canal; ring canal; radial canal; haversian canal

5. plankton; benthos; epifauna; infauna

1. Aristotle's lantern

2. resilium

3. ascus

4. choanocytes (collar cells)

5. cardinal process

1. "Lacy" bryozoans with zoaria characterized by zooecia arranged on ribbons connected by dissepiments. ________________________________

2. Now thought to be sclerosponges, they consist of laminae separated by pillars. ________________________________

3. Squid-like cephalopods with a well-calcified, bullet-shaped, internalized shell. ________________________________

4. echinoderms that attach to the substrate by columns and that have canals through the plates of the theca that connect pore rhombs. _____________________________________

5. Organisms of unknown affinities that are constructed as nested, perforated cones. _____________________________

1. Explain the difference between rheophilic and rheophobic crinoids. (10)

2. Echinoderms can be identified as such even from small fragments in thin section. What is it about echinoderms that makes their skeletal remains so distinctive? (5)

3. As a field geologist given responsibility for mapping a certain area you encounter a formation bearing the following fossils. What is your best estimate of its age and how did you come to this conclusion? (5)

4. From among the invertebrate groups we have studied, provide an example of groups that illustrate evolutionary convergence, and explain the reason for this phenomenon. (10)

5. What type of information is needed to employ graphic correlation in biostratigraphy according to the method developed by Shaw? How is it done? (10)

6. To what phylum are echinoderms most closely related? What features support this relationship? (10)

7. Explain how a fossil mold forms. (5)

8. Graptolites are widely considered to be chordates. What evidence from the graptolites themselves and from modern organisms supports this view? (5)

9. Jeffreys classifies one of the groups of homalozoan echinoderms as a chordate group he calls Calcichordata. What features of this echinoderm group might suggest such an interpretation? (5)

10. Reefs and reef-like structures have developed repeatedly throughout the history of life, but with different groups of organisms as the primary reef-builders. What groups have been the reef-builders and when throughout the Phanerozoic? (10)

11. What is the approximate stratigraphic range of each of the following groups?

12. On a profile of the ocean basin from land to the deep ocean indicate the location of the different marine ecological zones distinguished by depth. (10)

13. Use a eurypterid to diagram the basic body plan of the chelicerates. (10)

14. As a field geologist given responsibility for mapping a certain area you encounter a formation bearing the following fossils. What is your best estimate of its age and how did you come to this conclusion? (5)