AGROVOC Thesaurus
Terminology for agriculture, forestry, fisheries, food, and related fields (e.g., environment) in 17 languages (6 more in development). From the U.N.'s Food & Agriculture Organization.
Cold Spring Harbor Protocols
Research methods for microbiology, genetics, bioinformatics, proteins, plant biology, neuroscience, lab organisms, and imaging.
Grzimek's Animal Life Encyclopedia
Online version of the illustrated zoology encyclopedia. Includes insects and microflora. Current.