The Field Museum's Division of Environment, Culture, and Conservation (ECCo) has developed a Rapid Color Guide for Common Spiders of the Chicago Region. The guide and others can be viewed and downloaded for free from The Field Museum's website at http://fm2.fieldmuseum.org/plantguides/guideimages.asp?ID=472
The goal of Rapid Color Guides is to provide a set of free tools that help individuals quickly and accurately identify species in the field. The Guides often concentrate on a limited geographic area and may fill gaps in the published literature. If you have other ideas for new Rapid Color Guides, please contact firstname.lastname@example.org.