Vol. I. GENERAL KEY TO THE ORDERS AND FAMILIES. xxv 



Carpels 3 or more ; petals large ; floating leaves not dissected. 

 Carpels distinct. 



Carpels not in a receptacle. Fam. 26. Cabombaceae. 2 : 75. 



Carpels in a fleshy receptacle. Fam. 27. Nelumbonaceae. 2:76. 



Carpels united into a compound ovary. Fam. 28. Nymphaeaceae. 2 : 77. 



** Land or marsh plants (some Ranunculaceae aquatic). 



Stamens numerous; sepals distinct; petals present (except in some Ranunculaceae and in Calyco- 

 carpum of the Menispermaceae) . 

 Receptacle not hollow; leaves alternate (except in Clematis). 



Flowers perfect (except in some species of Clematis and Thalictrum) . 



Fruit aggregate, cone-like ; trees ; sepals and petals in 3 series, or more, of 3. 



Fam. 29. Magnoliaceae. 2 : 80. 

 Fruit not aggregate, the carpels separate, at least when mature. 

 Anthers not opening by valves ; pistils usually more than 1. 



Sepals 3 ; petals 6 ; shrubs or trees. Fam. 30. Annonaceae. 2 : 83. 



Sepals 3-15; petals (when present) about as many; our species herbs or vines 

 (Xanthorrhiza shrubby). Fam. 31. Ranunculaceae. 2:84. 



Anthers opening by valves (except in Podophyllum) ; pistil 1. 



Fam. 32. Berberidaceae. 2 : 126. 

 Dioecious climbing vines with simple leaves ; fruit drupaceous. 



Fam. 33. Menispermaceae. 2:130. 

 Receptacle hollow, enclosing the numerous pistils and achenes ; opposite-leaved shrubs. 



Fam. 34. Calycanthaceae. 2: 132. 



Stamens 9 or 12, in 3 or 4 series of 3 ; anthers opening by valves ; aromatic trees or shrubs with no 



petals, more or less united sepals, and 1 pistil. Fam. 35. Lauraceae. 2 : 133. 



2. Carpels 2 or more, united into a compound ovary; stamens hypogynous; sepals mostly distinct. 



* Plants not insectivorous. 



Order 13. Papaverales (Rhoeadales). 

 Sepals 2 (very rarely 3 or 4) ; endosperm fleshy. 



Flowers regular ; stamens 8-many. Fam. 36. Papaveraceae. 2:136. 



Flowers irregular; stamens 6. Fam. 37. Fumariaceae. 2: 141. 



Sepals or calyx-segments 4-8 ; endosperm none. 



Capsule 2-celled by a longitudinal partition, usually 2-valved, rarely indehiscent ; sepals and 

 petals 4. Fam. 38. Cruciferae. 2 : 146. 



Capsule 1 -celled, of 2-6 carpels. 



Sepals and petals 4, regular, or petals irregular; capsule of 2 carpels, 2-valved. 



Fam. 39. Capparidaceae. 2:196. 

 Sepals and petals 4-8, irregular; capsule of 3-6 carpels, 3-6-valved at the top ; disk large. 



Fam. 40. Resedaceae. 2 : 199. 



** Insectivorous plants, secreting a viscid liquid, with basal leaves and scapose flowers. 



Order 14. Sarraceniales. 

 Ovary 3-5-celled ; leaves hollow. " Fam. 41. Sarraceniaceae. 2:201. 



Ovary i-celled ; leaves circinate in unfolding, the blade flat. Fam. 42. Droseraceae. 2 : 202. 



3. Carpels solitary, or several and distinct, or sometimes united; stamens mostly perigynous or 



epigynous; sepals mainlyunited or confluent with the concave receptacle. Order 15. Rosales. 

 * Small aquatic fleshy herbs, with a spathe-like involucre, and a 2-3-celled capsule; perianth none. 



Fam. 43. Podostemaceae. 2 : 205. 



** Land or rarely swamp plants without an involucre. 



t Endosperm present, usually copious and fleshy. 



Herbaceous plants. 



Carpels as many as the sepals. 



Carpels distinct, or united below, longitudinally dehiscent ; succulent plants. 



Fam. 44. Crassulaceae. 2 : 205. 

 Carpels united to the midlde, circumscissile ; plants not succulent. 



Fam. 45. Penthoraceae. 2:211. 

 Carpels fewer than the sepals. 



Carpels 3 or 4, united into a i-celled ovary; staminodia present. 



Fam. 46. Parnassiaceae. 2:211. 

 Carpels mostly 2, distinct, or only partly united ; no staminodia. 



Fam. 47. Saxifragaceae. 2:214. 

 Shrubs or trees. 



Leaves opposite. Fam. 48. Hydrangeaceae. 2 : 230. 



Leaves alternate. 



Fruit a 2-5-celled capsule. 



Capsule thin-walled, almost free from the calyx-tube (hypanthium). 



Fam. 49. Iteaceae. 2 : 233. 

 Capsule woody, or thick-walled, adnate to the calyx-tube. 



Ovule solitary, suspended ; calyx-limb or calyx-limb and petals present. 



Fam. 50. Hamamelidaceae. 2 : 234. 

 Ovules several or numerous ; no calyx-limb nor petals. Fam. 51. Altingiaceae. 2:235. 

 Fruit a i-celled berry. Fam. 52. Grossulariaceae. 2:236. 



tf Endosperm none, or very little (copious in Opulaster, shrubs of the Rosaceae). 

 t Trees with broad leaves and small monoecious capitate flowers. 



Fam. 53. Platanaceae. 2 : 242. 



it Flowers perfect (dioecious in Aruncus and in species of Fragaria of the Rosaceae ; in Gleditsia 

 and Gymnocladus of the Caesalpiniaceae, and rarely in some Fabaceae). 



