328 THE KINDS OF PLANTS 



6. MAERtBITTM. Horehound. 



Erect perennials, with white-woolly aspect: calyx nearly equally 5-10- 

 toothed, the teeth very sharp: corolla 2-lipped, the upper lip erect and 

 notched, the lower one spreading and 3-lobed: stamens 4, included in the 

 corolla-tube. 



M. vulgare, Linn. Common horehound. Leaves broad-ovate and cre- 

 nate: flowers small, white, in dense whorls. Europe, but common. 



7. LEONtEUS. Motherwort. 



Erect perennials with green aspect: calyx about equally 5-toothed, the 

 teeth becoming spine-like: corolla 2-lipped, the upper lip somewhat arched 

 and entire, the lower spreading and 3-lobed: stamens 4, ascending under the 

 upper lip: nutlets 3-angled. 



L. Cardiaca, Linn. Common motherwort. Tall: leaves rounded and 

 lobed : corolla purple, the upper lip bearded : flowers in axillary whorls. 

 Introduced from Europe. Common. 



XXI. CONVOLVULACE^. Convolvulus Family. 



Herbs, mostly twining, with alternate chiefly simple leaves: 

 flowers regular, 5-merous, the tubular or trumpet-shaped corolla 

 mostly twisted in the bud, the stamens 5 and borne on the corolla: 

 ovary commonly 1-, mostly 2-loculed, with 2 ovules in each locule, 

 becoming a globular capsule in fruit (which is sometimes 4-loculed 

 by the insertion of a false partition). The family contains between 

 30 and 40 genera, and nearly 1,000 species. Common convolvulaceous 

 plants are morning-glory, cypress vine, sweet potato, bindweed, 

 dodder. 



a. Plants with normal foliage 1. Ipomaea 



aa. Plants leafless, parasitic 2. Cuscuta 



1. IPOMCEA. Morning-glory. 



Mostly twining, with showy flowers on axillary peduncles : 

 corolla with a long tube and a flaring limb: pistil 1, with one 

 style, and the stigma 2-3-lobed: fruit a capsule, with 1-seeded 

 locules. 



a. Leaves compound, with, thread-like divisions. 



I. Quamoclit, Linn. Cypress vine. Fig. 485. Leaves pin- 

 nate: flowers solitary, red, small, narrow-limbed, with pro- 

 jecting style and stamens. Tropical America, but run wild 

 South; also cultivated. Annual. 



aa. Leaves simple or deeply lobed, broad. 



I. B6na-N6x, Linn. White moonflower. Fig. 486. Tall: 4 g 5 ip 0rucea 

 leaves heart-shaped, or angled or lobed: flowers 1 to few, Quamoclit. 



