192 KEY AND FLORA 



4-8-lobed. Stamens 4-8, inserted on the corolla tube; 'fila- 

 ments thread-shaped ; anthers facing inwards. Ovary 1-2- 

 celled ; ovules many, on 2 opposite placentas. Capsule 1-celled 

 or partially 2-celled, 2-valved, many-seeded. [The best known 

 genus, Gentiana, consists mainly of autumn-flowering species.] 



I. OBOLARIA L. 



A low, smooth, purplish-green perennial. Flowers axillary 

 and terminal. Calyx of 2 distinct, spatulate, bract-like sepals. 

 Corolla tubular-bell-shaped, 4-lobed. Stamens short, inserted 

 at the notches of the corolla. Style short; stigma 2-lipped. 

 Capsule ovoid, more or less 2-4-celled ; seeds very minute 

 and numerous. 



1. 0. virginica L. Pennywort. Stem 3-8 in. high, often several 

 from the same root. Leaves somewhat fleshy, wedge-obovate or 

 somewhat diamond-shaped, often truncate, sessile. Flowers opposite 

 or terminal in threes, nearly sessile. Corolla pale purple or nearly 

 white. Rich woodlands, among dead leaves; 



II. MENYANTHES L. 



Perennial, scape-bearing marsh herbs. Rootstock creeping. 

 Leaves of 3 leaflets. Flowers racemed. Calyx 5-parted. 

 Corolla fleshy, funnel-shaped, the limb 5-parted. Stamens 5, 

 inserted on the corolla tube. Disk of 5 liypogynous glands. 

 Ovary 1-celled ; style thread-shaped ; stigma 2-lobed. Capsule 

 globose, many-seeded. 



1. M. trifoliata L. Buck Bean, Marsh Trefoil. Rootstocks 

 stout and matted. Leaflets obtuse, entire. Flowers f in. in diameter, 

 white or pinkish. Bogs, esj^ecially N. 



8L APOCYNACE^. Dogbane Family 



Trees, shrubs, or herbs, with milky juice, often climbing. 

 Leaves usually opposite, rarely whorled, entire, nearly or 

 quite without stipules. Flowers actinomorphic, solitary or in 

 cymes. Calyx 4-5-cleft. Corolla hypogynous, funnel-, salver-, 

 or bell-shaped, sometimes with scales in the throat. Stamens 

 4-5, borne on the corolla tube or throat ; filaments very short ; 



