• Animal Sciences. This interdisciplinary resource explores the wide-ranging diversity that exists within the animal kingdom.
• Beacham's Guide to the Endangered Species of North America. Presents extensive data on the habitats and ecosystems of more than 1,200 species identified as endangered or threatened by the U.S. Fish and Wildlife service.
• Biology. A comprehensive collection of articles on all aspects of biological science, including its history and issues. Includes articles on biology-related careers and important individuals, as well as topics from active transport to zoology research.
• Encyclopedia of Bioethics. 3rd ed. Covering topics on the ethics of health professions, animal research, population control and the environment.
• Endangered Species: protecting biodiversity
• Environmental Encyclopedia. Provides in-depth, worldwide coverage of environmental issues. Each article is written in a nontechnical style and provides current status, analysis, and suggested solutions whenever possible.
• Environmental Issues: Essential Primary Sources
• Genetics. A comprehensive collection of articles on all aspects of genetics, from Mendel to the decoding of the human genome.
• Grzimek's Animal Life Encyclopedia. Nearly 10,000 pages long. Incorporates recent developments in the animal world as noted by prominent advisors and contributors from the scientific community.
• Oxford Reference Online: Biological Sciences
• Plant Sciences - a collection of articles on all aspects of plant sciences
• World of Microbiology and Immunology
  
  
• All About Birds - from the Cornell Lab of Ornithology
• The Biology Project - "an online interactive resource for learning biology"
• eNature.com- from the National Wildlife Federation. Field guides, birding, parks & refuges, etc.
• EncycloZine: Biology - a free online encyclopedia.
• NatureServe Explorer - "an online encyclopedia of life." Search by plant/animal name or ecological community/system. Covers U.S. and Canada, with a related site for Latin America. Good bibliographies.
• PlantFacts - from Ohio State Univ.
• 123Genomics.com - "a Genomics, Proteomics and Bioinformatics Knowledge Base"

In print in Crumb Library reference collection:

• McGraw-Hill Encyclopedia of Science and Technology. 20 v. (Ref Q 121.M3 1997)
• Life on Earth. (Ref QH 541.15.B56L54 2002)
• Molecular Biology and Biotechnology: a comprehensive desk reference. Ref QH 506.M66I55 1995
• Encyclopedia of Human Biology. (Ref QP 11.E53 1991)
• Encyclopedia of Environmental Biology (Ref QH 540.4.E52 1995)
• Official World Wildlife Fund guide to Endangered Species of North America. 3 v. 1990. (Ref QL 84.2.O35 1990)
• Grzimek's Animal Life Encyclopedia. (Ref QL 7.G7813 2003)
• Walker's Mammals of the World. 6th ed. 2 v. (Ref QL 703.W222 1999)
• Gray's Anatomy. 38th ed. 1995. (Ref QM 23.2.G73 1995)