This document provides an overview of the natural system of plant classification developed by George Bentham and Joseph Dalton Hooker in their book Genera Plantarum. It describes the key features of their system, including dividing plants into two major groups - cryptogams (non-flowering plants) and phanerogams (flowering plants). Flowering plants are further divided into dicotyledons, monocotyledons, and gymnosperms. The system places plant families into a hierarchical structure of orders, cohorts, and series based on morphological characteristics. While pioneering for its time, the system is not fully phylogenetic and has limitations such as not clearly addressing the origin of angiosperms.

1. Sharad Suresh Kambale
Assistant Professor,
Department of Botany,
Maratha Vidya Prasarak Samaj’s Arts, Commerce
& Science College, Tryambakeshwar,
Nashik- 422212.
Email: skambalesu@gmail.com
Contact no.: 09623127314
Natural system of classification by
Bentham and Hooker

2. Natural system of classification according to Bentham and Hooker
George Bentham (1800-1884) Joseph Dalton Hooker(1817-1911)

3. Introduction:
 Artificial system of classification found to be irrational.
 Comparative morphology is important to determine relationships.
 System which reflects the natural affinities in plants is known as
‘Natural system of Classification’.
 George Bentham & Joseph Dalton Hooker, two British botanists
published ‘Genera plantarum’.
 They provided the natural system of classification in their book.
 Names, description and classification of 200 families, 7569 genera
and 97205 species have been given.
 Larger genera subdivided into subgenera and sections.
 They used term ‘Order’ for ‘Family’ and ‘Cohort’ for ‘Order’.

4. Kingdom plantae
Cryptogamia (Non-flowering
plants) Phanerogamia (flowering plants)
Dicotyledonae (two Cotyledons) Gymnosperms Monocotyledonae (one Cotyledon)

5. Algae
Fungi
Lichen Bryophytes
Pteridophytes
Division: Cryptogamia

7. (Corolla of separate petals)
1. Ranales
2. Parietales
3. Polygalineae
4. Caryophyllineae
5. Guttiferales
6. Malvales

8. Series- Thalamiflorae (Stamens hypogynous and many)
Cohort/Order 1:Ranales (Gynoecium usually apocarpous)
Annonaceae Dilleniaceae
Mangnoliaceae
Menispermaceae

9. Cohort / Order2: Parietales (Placentation parietal)
Papaveraceae
Brassicaceae
Capparidaceae Violaceae Cistaceae Parietal Placentation

10. Cohort/Order 3: Polygalineae (Ovary 2 locular)
Pittosporaceae
Polygalaceae
Polygalaceae

11. Cohort/Order 4: Caryophyllineae (Placentation free central or axile)
Portulacaceae
Tamaricaceae
Caryophyllaceae

12. Cohort/Order 5: Guttiferales
(Stamens many, sepals imbricate)
Dipterocarpaceae Elatinaceae
Clusiaceae
Hypericaceae

13. Cohort/Order 6: Malvales (Stamens many, sepals valvate)
Sterculiaceae
Bombacaceae
Malvaceae

14. Series 2: Discifloreae
Hypogynous disc often present.
 Stamens definite.
 As many as or twice the petals.
Cohort/ Order 7: Geraniales (Androecium
obdiplostemonous, ovules pendulous, raphe ventral)
Linaceae Ochnaceae Rutaceae
Meliaceae
Burseraceae

15. Cohort/ Order 8: Olacales (Androecium
diplostemonous, ovules pendulous, raphe dorsal)
Olacaceae
Olacaceae

16. Cohort/ Order 9: Celastrales (Androecium
haplostemonous, ovules erect, raphe ventral)
Celastraceae
Rhamnaceae

17. Cohort/ Order 10: Sapindales (Androecium diplostemonous,
ovules ovules ascending, raphe ventral or inverted)
Sapindaceae Anacardiaceae

18. Ordines anomali
Moringaceae

19. Series 3: Calycifloreae
Sepals united.
 Stamens peri or epigynous.
Cohort/ Order 11: Rosales
(Stamens indefinite, often twice
or more the number of petals,
styles distinct).
Rosaceae
Connaraceae
Leguminosae
Droseraceae
Crassulaceae

20. Cohort/ Order 12: Myrtales (Stamens definite, rarely
indefinite, flowers peri or epigynous).
Myrtaceae Rhizophoraceae
Combretaceae
Onagraceae
Lythraceae

21. Cohort/ Order 13: Passiflorales (Placentation parietal).
Passifloraceae Cucurbitaceae
Turneraceae Begoniaceae

22. Cohort/ Order 14: Ficoidales (Perianth undifferentiated, ovules on axile
or basal placentation).
Cactaceae
Molluginaceae

23. Cohort/ Order 15: Umbellales (Inflorescence umbellate).
Apiaceae Araliaceae

24. Subclass Gamopetalae (Corolla of united petals).
Series 4: Inferae (Stamens as many as petals and alternating with them,
ovary inferior).
Cohort/Order 16: Rubiales (Stamens epipetalous, anthers distinct, ovary
2- many locular, locules 1- many ovuled)
Rubiaceae

25. Cohort/Order 17: Asterales (Stamens epipetalous, anthers distinct or united, ovary 1
locular, locules 1 ovuled)
Asteraceae

26. Cohort/Order 18: Campanulales (Stamens not adnate to corolla, ovary 2-6 locular,
locules many ovuled)
Lobeliaceae Stylidiaceae

27. Series 5 Heteromerae (Stamens as many as corolla lobes or many, ovary superior or
inferior, carpels more than 2, generally isomerous with corolla lobes).
Cohort/Order 19: Ericales (Stamens twice the corolla lobes or isomerous and
alternating with them).
Ericaceae Vacciniaceae

28. Cohort/Order 20: Primulales (Stamens twice the corolla lobes or
isomerous and alternating with them).
Primulacae Plumbaginaceae

29. Cohort/Order 21: Ebenales (Stamens as many as corolla lobes
or many and opposite with them).
Ebenaceae
Sapotaceae
Symplocaceae

30. Series 6 Bicarpellate (Stamens as many as corolla lobes
and or few and alternate with them, ovary usually bicarpellary
and superior).
Cohort/Order 22: Gentianales (Corolla
actinomorphic, leaves usually opposite).
Gentianaceae
Salvadoraceae
Apocynaceae
Oleaceae

31. Cohort/Order 23: Polemoniales
Corolla actinomorphic.
Leaves usually alternate.
Convolvulaceae Boraginaceae Hydrophyllaceae
Solanaceae

32. Solanaceae

33. Cohort/Order 24: Personales
Corolla Zygomorphic .
Posterior stamens usually reduced to
staminodes.
 Ovules often more than 4.
Martyniaceae
Bignoniaceae
Bignoniaceae

34. Acanthaceae
Acanthaceae Lentibulariaceae

35. Cohort/Order 25: Lamiales
Corolla Zygomorphic .
Posterior stamens reduced.
 Ovules 4.
Verbenaceae
Lamiaceae
Lamiaceae

36. Subclass Monochlamydeae (Perianth 1 or biseriate, mostly sepaloid, minute or
absent)
Series 7: Curvembryeae (Seeds usually with mealy endosperm, embryo curved,
lateral or peripheral; ovary usually single ovuled)
Amaranthaceae Chenopodiaceae Polygonaceae

37. Series 8: Multiovulatae aquaticae
Immersed aquatic herbs,
Ovary syncarpous,
Ovules many.
Podostemaceae

38. Series 9: Multiovulatae terrestris
Terrestrial herbs,
Ovary syncarpous,
Ovules many.
Aristolochiaceae
Nepenthaceae

39. Series 10: Micrembryeae
Carpels 1 to 2 ovuled,
Ovules with copious endosperm and minute embryo.
Piperaceae Myristicaceae

40. Series 11. Daphnales
Ovary monocarpellary,
rarely syncarpous and 2 to 4 ovuled,
Plants woody or herbaceous,
Perianth mostly sepaloid, stamens,
perigynous
Thymelaeceae Lauraceae
Elaegnaceae

41. Series 12. Achlamydosporeae
Ovary 1 locular, 1 to 3 ovuled,
Seeds endospermic , without testa .
Santalaceae
Loranthaceae
Loranthaceae
Viscaceae

42. Series 13. Unisexuales
Flowers strictly unisexual or
polygamous,
Seeds endospermic ,
without testa .
Euphorbiaceae
Casuarinaceae Ulmaceae

43. Series 14: Ordines anomali
Salicaceae Ceratophyllaceae

44. Class Gymnospermae
Order 1. Gnetaceae
Coniferae
Cycadaceae

45. Class Monocotyledons (One Cotyledon)
Series 15 Microspermae (Inner perianth
petalod, ovary inferior, seeds minute and
nuerous)
Burmanniaceae
Orchidaceae
Hydrocharitaceae

46. Series 16 Epigyneae (Inner perianth
petaloid, ovary inferior, ovules large
and few to many )
Bromeliaceae Musaceae
Taccaceae
Dioscoreaceae

47. Series 17 Coronarieae
Inner perianth petaloid).
Liliaceae
Xyridaceae
Commelinaceae

48. Series 18 Calycinae
Inner perianth sepaloid, rigid or herbaceous).
Juncaceae Arecaceae

49. Series 19 Nudiflorae
Perianth reduced
or absent
Pandanaceae
PandanaceaeTyphaceae
Lemnaceae Araceae

50. Series 20 Apocarpae
Perianth 1 to 2 seriate or absent,
Carpel solitary or apocarpous,
 Seeds non-endospermic
Aponogetonaceae Alismataceae

51. Series 21 Glumaceae
Flowers in dense inflorescences
subtended by bracts or glumes,
 Perianth reduced, glumaceous or
absent
 Ovary one loculed with one ovule
Cyperaceae Poaceae
Eriocaulaceae

52. Merits:
 First ad best natural system.
 Easy to understand and most connvinient in the field.
 The position of Discifloreae in between Thalamifloreae and
Calycifloreae is acceptable.
 The place of order Ranales is rational.
 Monocots are placed after dicots which shows they are derived
from dicots which is acceptable

53. Limitations:
 Its not phylogenetic.
 Many important floral characters are not considered.
 Gymnosperms are kept in between dicot and monocot which is not
correct.
 Closely related families have been widely separated and vice-versa.
eg. Chenopodiaceae and Caryophylaceae are kept away from each other.
Monochlamydeae is kept away from polypetalae.
Monochlamydeae has not been subdivided into series but direct orders.
Apocarpae in monocot should have been placed in thebeginning.
 Orchidaceae and Scitamineae which are with many advanced characters
are kept in the beginning.
 Origin of Angiosperms is not clear.

54. Thank you