CHARACTERISTICS OF NATURAL ORDERS. 189 



2 placentse, seeds co. Herbs with opposite, entire leaves, without 

 stipules. 260. 



54. Polemoniaceae. Flowers 5-merous, ovary 3-celled, and style 

 3-cleft. Herbs with alternate leaves, without stipules. 261. 



55. Boraginaceae. Inflorescence scorpioid ; flowers 5-merous, 

 with 4-lobed ovary becoming 4 achenes ; style I. 262. 



56. Convolvulaceae. Flowers 5-merous, corolla convolute, ovary 

 2-celled, i-styled ; embryo large, crumpled. Twining or trailing 

 herbs. 264. 



57. Solanaceae. Flowers 5-merous, on bractless pedicels ; ovary 

 2-celled, co-seeded ; pod or berry. Mostly narcotic herbs. 265. 



Inferior Gamopetalous Exogens with Irregular Flowers. 



58. Scrophulariaceae. Flowers 2-lipped, stamens 2 or 4, didyna- 

 mous ; ovary 2-celled, single style, placentae axile, seeds oo. Chiefly 

 herbs. 267. 



59. Lentibulaceae. Stamens 2, ovary i-celled. Floating herbs. 

 272. 



60. Bignoniaceae. Stamens 2 or 4 ; seeds co, winged. Trees or 

 shrubs with opposite leaves. 272. 



61. Verbenaceae. Stamens 2-4, ovary 4-celled. Herbs or shrubs 

 with opposite leaves. 273. 



62. Labiatae. Stamens didynamous, ovary 4-lobed, becoming 4 

 nutlets. Herbs with square stems and opposite leaves. 274. 



63. Plantaginaceae. Flowers spiked, 4-merous ; stamens epipet- 

 alous, anthers versatile. 280. 



Apetalous Exogens with Perfect Flowers. 



64. Nyctaginaceae. Perianth petaloid, united at base, inclosing 

 the fruit ; ovary i-celled, i-seeded utricle. 281. 



65. Amarantaceae. Flowers in dense clusters ; stamens united 

 at base ; ovary i-celled ; fruit a utricle. 281. 



66. Chenopodiaceae. Like 65, perianth green ; filaments not 

 united. Leaves often mealy. 282. 



67. Phytolaccaceae. Inflorescence racemose ; stamens hypogy- 

 nous. Leaves alternate, glabrous. 283. 



68. Polygonaceae. Ovary i-celled, styles 2-3, and i orthotropous 

 seed. Leaves alternate, with membranous sheathing stipules. 283. 



69. Aristolochiaceae. Ovary 4-6-celled, seeds co. Herbs or 

 shrubs, often twining. 285. 



70. Lauraceae. Sepals 4-6 in two rows, anthers opening by 

 valves. Aromatic trees or shrubs with punctate leaves. 285. 



