Trilobites

http://www.trilobites.info/trilobite.htm

http://www.paleodirect.com/trilobites.htm

http://www.nmnh.si.edu/paleo/shale/polen.htm

http://www.fossilmuseum.net/Tree_of_Life/Phylum%20Arthropoda/ClassTrilobita.htm

http://www.nmnh.si.edu/paleo/shale/pnara.htm

http://www.museum.vic.gov.au/prehistoric/time/trilobites.html

http://www.shgresources.com/wi/symbols/fossil/

http://www.oum.ox.ac.uk/thezone/fossils/inverts/trilo.htm

Trilobites and their general environment

http://www.trilobites.info/triloecology.htm