GENERAL KEY TO THE ORDERS AND FAMILIES. xni 



Series 2. Gamopetalae. 2:548103:493. 



relals more or less united. (See exceptions noted on page 548, Vol. 2. ) 



A. Ovary superior (except in Vacciniaceae and Symplocaceae, in which it is partly or wholly 



inferior. ) 



I. Stamens mostly free from the corolla, or adnate merely to its base (at the sinuses of the corolla 



in Diapensia and Pyxidanlhcra of the Diapensiaceae), as many as the lobes and 

 alternate with them, or twice as many. Order 1. Ericales. 



Stamens free from the corolla, or merely annate to its base, not united into a tube. 

 Ovary superior; fruit a capsule, or rarely drupaceous. 

 Corolla essentially polypetalous. 



Ovary 3-eelled; shrubs; leaves deciduous. Fam. 1. Clethraceae. 2: 548 



Ovary 4-5 celled; low, mostly evergreen perennials. Fam. 2. Pyrolaceae. 2:549 



Corolla distinctly gamopetalous (except in Monotropa and Hypopilys of the Monotropaceae 

 and Ledum of the Ericaceae). 

 Herbaceous saprophytes without green leaves. Fam. 3. Jfonotropaceae. 2: 554 



Shrubs with normal, often evergreen leaves. Fam. 4. Ericaceae. 2: 556 



Ovary inferior, adnate to the calyx, forming a many-seeded berry in fruit. 



Fam. 5. Vacciniaceae. 2: 573 

 Stamens borne at the sinuses of the corolla, or united in a iolobed tube. 



Fam. 6. Diapensiaceae. 2: 582 



II. Stamens borne on the corolla, as many as its lobes and opposite them, or twice as many, or more 

 Herbs. Order 2. Primulales. 



Style 1 ; fruit a capsule. Fam. 7. Primulaceae. 2:584 



Styles 5; fruit an achene or utricle. Fam. 8. Plumbaginaceae. 2: 594 



Shrubs or trees. Order 3. Ebenales. 



Stamens as many as the corolla-lobes. Fam. 9. Sapotaceae. 2: 595 

 Stamens twice as many as the corolla-lobes, or more. 



Styles 2-8; flowers mostly monoecious or dioecious. Fam. 10. Ebenaceae. 2:596 

 Style 1, simple or lobed; flowers mostly perfect. 



Stamens in several series. Fam. n. Symplocaceae. 2:597 



Stamens in 1 series. Fam. 12. Styracaceae. 2:598 



III. Stamens borne on the corolla, as many as its lobes or fewer, and alternate with them (In our 



species of Fraxinus and Adelia of the Oleaceae there is no corolla). 



* Corolla not scarious, nerved. 



f Ovaries 2, distinct (except in some Loganiaceae, and in Gentianaceae and Menyanthaceae, in 

 which the ovary is compound, with 2 cavities, or rarely more, or with 1 cavity and 2 

 placentae); flowers regular; stamens mostly adnate to only the lower part 

 of the corolla; leaves mostly opposite. 



Order 4. Gentianales (Contortae). 



a. Stamens (usually 2), fewer than the corolla-lobes, or corolla none; our species 



trees or shrubs. Fam. 13. Oleaceae. 2:600. 



b. Stamens as many as the corolla-lobes; mostly herbs. 



Stigmas distinct; juice not milky; ovary 1, compound. 



Ovary 2-celled; leaves stipulate, or their bases connected by a stipular line. 



Fam. 14. Loganiaceae. 2: 604. 

 Ovary i-celled; leaves not stipulate. 



Leaves opposite or rarely verticillate; corolla-lobes convolute or imbricated in the bud. 



Fam. 15. Gentianaceae. 2: 606. 

 Leaves basal or alternate; corolla-lobes induplicate-valvate in the bud; marsh or aquatic 

 herbs. Fam. 16. Menyanthaceae. 2: 621. 



Stigmas united; juice milky; ovaries 2 in our species. 



Styles united; stamens distinct; pollen of simple grains. Fam. 17. Apocynaceae. 3: 1. 



Styles distinct; stamens mostly monadelphous; pollen-grains united into waxy masses. 



Fam. 18. Asclepiadaceae. 3: 4. 

 It Ovary 1, compound (2-divided in Dichondra of the Convolvulaceae; in Boraginaceae and Labi- 

 atae mostly deeply 4-lobed around the style) flowers regular or irregular; stamens mostly 

 adnate to the middle of the corolla-tube or beyond; leaves opposite or alternate. 



Order 5. Polemoxiales ( Tubiflorae). 



a. Corolla regular (irregular in Echium of the Boraginaceae). 



Ovary not 4-lobed, the carpels not separating as separate nutlets at maturity. 



Ovary 2-celled, rarely 3-4-celled; style 1, entire, 2-cleft, or 2-parted; mostly twining vines. 



Leaves normal. Fam. 19. Convolvulaceae. 3: 19. 



White or yellowish parasitic vines, the leaves reduced to minute scales. 



Fam. 20. Cuscutaceae. 3: 27. 

 Ovary 3-celled; stigmas 3, linear; herbs, not twining. Fam. 21. Polemoniaceae. 3:31. 



Ovary i-celled (2-celled in Nama); style I, 2-lobed, or 2-parted; herbs, not twining. 



Fam. 22. Hydrophyllaceae. 3: 43. 

 Ovary deeply 4-lobed around the style, or not lobed {Heliotropium)\ carpels separating as nutlets. 



Fam. 23. Boraginaceae. 3: 50. 



b. Corolla irregular, more or less 2-lipped (regular in Solanaceae, in Mentha and Lycopus of the 

 Labiatae, and nearly or quite so in Verbena and Callicarpa of the Verbenaceae). 



1 . Carpels 1-2-seeded. 



Ovary not lobed, 2-4-celled, the style apical; carpels separating into 1 -seeded nutlets. 



Fam. 24. Verbenaceae. 3: 69. 

 Ovary 4-lobed around the style, the lobes ripening into i-seeded nutlets. 



Fam. 25. Labiatae. 3: 74. 



