A taxonomic system for seed plants was published in Bentham and Hooker's Genera plantarum ad exemplaria imprimis in herbariis kewensibus servata definita in three volumes between 1862 and 1883. George Bentham (1800–1884) and Joseph Dalton Hooker (1817–1911) were British botanists who were closely affiliated to the Royal Botanic Gardens, Kew, in England. Their system of botanical taxonomy was based on the principle of natural affinities and is considered as pre-Darwinian as it does not take evolution into account. The Genera plantarum classified an estimated 97,205 species into 202 families and 7,569 genera.

Summary

The system recognises the following main groups:

Families and orders in the Bentham & Hooker system

Note that this system was published well before there were internationally accepted rules for botanical nomenclature. It indicates a family by "ordo"; an order is indicated by "cohors" (in the first two volumes) or "series" (in the third volume); in the first two volumes “series” refers to a rank above that of order. Terminations for families are not what they are now. Neither of these phenomena is a problem from a nomenclatural perspective: the ICBN provides for this

Dicotyledonae

Dicotyledonae

Gymnosperms

1> Gnetaceae 2> Coniferae 3> Cycadaceae

Monocotyledons

Monocotyledons

Series I. Microspermæ p. 448

Series II Epigynæ p. 636

Series III Coronarieæ p. 746

Series VI Calycineæ p. 860

Series V. Nudifloreæ p. 949

Series VI. Apocarpæ p.1001

Series VII. Glumaceæ p. 1019