The Illinois Natural History Survey Home Page is a good place to become acquainted with the ecosystems of Illinois. At this site you will find material about the flora and fauna of the state, and the projects the Illinois Natural History Survey is conducting to preserve them. You can also link to the various collections held there, including the entomology collection (over 6,000,000 strong), the herbarium, 645,000 fish specimens, a crustacean collection, and a collection of mollusks. The various centers which comprise the Survey are linked as well. Among them are the Center for Aquatic Ecology, the Center for Biodiversity, and the Center for Economic Entomology. You can wander over to the library and peruse publications produced by the Survey or written by Survey staff members. Whether your metier involves exotic crayfish, immature mosquitoes, prairie chickens or aquatic worms, this site has something intriguing for you.