A. Shell without transverse partitions or sutures 1. Shell coiled like ram’s horn, low spired; shell has two valves, smaller flattened valve often missing. In Texas exclusively Cretaceous Pelecypod 2. Shell tightly coiled, most have higher spire than 1, shell smaller and not as rough as 1, has only one valve Gastropod B. Coiled fossils, coiling not in one plane 1. Shell with transverse internal partitions or sutures a. Partitions always smooth, thick shelled, loosely and irregularly coiled, in Texas exclusively Cretaceous Caprinid b. Partitions (sutures) generally wrinkled, regularly and tightly coiled Cephalopod 2. Shell without transverse internal partitions or sutures Gastropod 3. Solid spiral ridge around central axis, resembles corkscrew Bryozoan C. Uncoiled fossils 1. Fossil resembles narrow saw blade. Paleozoic only Graptolite 2. Fossil irregularly cone-shaped, longitudinal partitions or septa Coral 3. Shell resembles clam or oyster, nonsymmetrical Pelecypod (mostly oysters) 4. Branching twig-like fossils a. Covered with minute pores or openings Bryozoa b. With evenly distributed larger openings with septa Colonial coral 5. Lace-like fossils, occur as thin sheets or films Bryozoa 6. Masses of circular or polygonal tubes with septa Colonial coral 7. Irregular fossils, cylindrical with rough surface a. Large axial opening with thick wall, external longitudinal ribs. Cretaceous only Rudistid b. Solid, no opening, small pits or pores. Pennsylvanian or Permian Sponge CATALOGING THE COLLECTION After the fossils have been cleaned and tentatively identified, they should be cataloged. This is necessary to enable the collector to have a record of his collection and to furnish as much information as possible about each individual fossil.