Berkeley Natural History Museums
California Native Plant Society
Green Plant Phylogeny Group. This is a consortium of botanical systematists working
     towards the common goal of producing a phylogeny of green plants by the end of the millenium.
Oakland Museum
San Francisco Estuary Institute
SETI Institute
University of California Botanical Garden

Professional Societies and Organizations for the Study of Evolution and Systematics

American Institute of Biological Sciences (AIBS)
American Society of Plant Taxonomists (ASPT)
Australian Systematic Botany Society (ASBS)
European Society for Evolutionary Biology (ESEB)
International Society for Biochemical Systematics (ISBS)
Linnean Society of London
Society for Integrative and Comparative Biology   Formerly the American Society of Zoologists.
Society for Molecular Biology and Evolution (SMBE).   International society for molecular evolutionists.
Society for the Study of Evolution (SSE)
Society of Systematic Biologists (SSB)
Willi Hennig Society   This society is an international organization for cladistic biologists.

Biodiversity and Biological Collections Web Server
Organization of Biological Field Stations