Biology
General Websites
BioTech - "Life sciences resources and reference tools"
Biozone Biolinks -- Extensive collection, from New Zealand
Life Sciences -- From the Internet Public Library
Specific Aspects
AGRICOLA -- From National Agricultural Library
" The Bad Bug Book" -- Foodborne Pathogenic Microorganisms and Natural Toxins Handbook, US FDA
Centers for Disease Control & Prevention -- The premier U.S. source for information and research about disease
Cetacea -- Information about whales, dolphins, & porpoises
DNA
eNature.com -- Searchable field guides to over 4,800 plant and animal species
EnviroLink -- "The largest online environmental information resource on the planet."
eSkeletons -- The Virtual Skeletons Project, from the University of Texas
National Plants Database -- Search by common name, scientific name, family, or genus; limit by state; etc.
The Tree of Life -- A distributed Internet project about phylogeny and biodiversity