12 



KEY TO THE FAMILIES. 



12. 

 12, 



14. 

 14. 



9. At least the staminate flowers in aments, or ament-like spikes 



or heads, - - - - - - - - - -10 



9. Staminate flowers not in aments, - - - - - - -12 



10. Leaves simple, ----------- H 



10. Leaves pinnately compound; fruit a nut surrounded by a hard or 



fibrous husk, --------- 48 Juglandaceae 



11. Fruit a nut, surrounded by a scaly or spiny involucre, 



(cup or burr.) ------- -52 Fagaceae 



11. Fruit a syncarp or syconium, 55 Artocarpaceae 



Ovary superior or partly inferior, - - - - - - - 13 



Ovary inferior, -----------33 



13. Style and stigma 1, - --------14 



13. Styles or stigmas 2-several, --------17 



Leaves pinnately-parted; shrubs or trees, - 121 Proteaceae 



Leaves entire or lobed, --------- 15 



15. Herbs or shrubs; flowers often bracted; fruit an achene, 62 Allionaceae 

 15. Herbs, sometimes shrubby, flowers without bracts; fruit an 



achene, --------- 53 Urticaceae 



15. Shrubs or trees; flowers without bracts; fruit a drupe, - - - 16 

 16. Anthers opening by slits; leaves silvery below, - - 122 Eleagnaceae 

 16. Anthers opening by valves, ------ 123 Lauraceae 



17. Ovary 1-celled, 18 



17. Ovary with two-several cells or placentae, more than 1 ovuled, - - 27 

 18. Leaves with sheathing stipules, or if without stipules fruit a 3-angled 



achene, ---------57 Polygonaceae 



18. Leaves without stipules, or stipules not sheathing, and fruit not 



a 3-angled achene, - - - - - - - - - 19 



19. Shrubs or trees, ----------20 



19. Herbs, sometimes shrubby, or vines, ------ 21 



20. Anthers opening lengthwise, - - - - - - -56 Ulmaceae 



20. Anthers opening by valves, ------ 123 Lauraceae 



21. Leaves compound; chiefly vines, 69 Ranunculaceae 



21. Leaves simple, 3-7 lobed; twining herbs, — — — 54 Cannabinaceae 

 21. Leaves simple; no vines and not twining, ----- 22 



22. Plants without acrid or milky juice, _______ 23 



22. Plants with acrid, often milky, juice, - - - - 101 Euphorbiaceae 



23. Fruit a capsule with valvular dehiscence, - - 64 Tetragoniaceae 

 23. Fruit a utricle, berry, or achene, -------24 



24. Stipules wanting, ----------- 25 



24. Stipules present, -------- 60 Corrigiolaceae 



25. Flowers without scarious bracts, -------26 



25. Flowers with scarious, often colored, bracts, - - 59 Amaranthaceae 

 26. Fruit a utricle or an achene, - - - - - 58 Chenopodiaceae 



26. Fruit a berry, -------- 61 Phytolaccaceae 



27. Stamens hypogynous, --------- 28 



27. Stamens perigynous or epigynous, -------32 



28. Herbs, rarely shrubs or trees, --------29 



28. Shrubs or trees, ___-_--- 141 Oleaceae 



29. Flowers monoecious or dioecious, _ - - 101 Euphorbiaceae 



29. Flowers perfect, 30 



30. Stamens tetradynamous, ovary 2-celled, - - - - 76 Brassicaceae 

 30. Stamens not tetradynamous, ovary several-celled, - - - - - 31 



