Online Tools for Plant Taxonomy

Index Herbariorum.  Part I.  Herbaria of the World -- The place to go for information on herbaria.

Index Nominum Genericorum -- Generic names with place of publication and nomenclatural status.

Index Nominum Supragenericorum Plantarum Vascularium -- Information on names of taxa above the level of genus.

Index of Botanists (Harvard) -- Information about plant name authors, collectors, and authors of publications.

Index of Botanical Publications (Harvard) -- Information about botanical journals and books.

International Plant Names Index -- An amalgamation of the Gray Index, Index Kewensis, and the Australian Plant Names Index.

Kew Record of Taxonomic Literature -- An index to taxonomic literature.

Names in Current Use for Extant Plant Genera -- A listing of currently accepted names at the generic level.

W³ Tropicos database -- Information on published plant names (place of publication, author, etc.)