DICOTYLEDONS. 199 



white, about half the length of the calyx. May -June. In dry fields 

 and thickets. 



'2. O. ViRGiNiANUM (L.) DC. Virginia Gromwell. Stem 

 erect, slender, sparingly branched above, rough with bristly hairs, 

 1-2 ft. high ; leaves kmceolate to oblanceolate, obtuse at the apex, 

 sessile ; corolla yellowish-white, tubular, the lobes acute, nearly as 

 long as the tube, bristly ; nutlets white, shining, ovoid. May-June. 

 In dry fields and woods. 



109. VERBENACE^. VERBENA FAMILY. 



Herbs or shrubs ; stems 4-angled ; leaves simple or com- 

 pound, exstipulate ; flowers perfect, terminal or axillary, in 

 spikes, racemes or panicles ; calyx 4-5-parted, persistent ; 

 corolla regular or 2-lipped, 4-5-lobed ; stamens 2, 4, or 5, in- 

 serted in the tube of the corolla; ovary free, 2-8-celled, 1 

 or 2 ovules in each cell, style simple, terminal ; fruit dry 

 and separating into several 1-seeded nutlets, or baccate. 



I. VERBENA. 



Annual or perennial herbs ; leaves simple, opposite, ser- 

 rate or pinnately lobed; flowers in terminal spikes w^hich 

 become much elongated in fruit ; calyx tubular, 5-ribbed, 

 5-toothed ; corolla salver-form or funnel-form, the tube often 

 curved, bearded in the throat, limb spreading, 5-lobed, often 

 somewhat 2-lipped ; stamens 4, didynamous, rarely only 2, 

 included; ovary 2-4-celled, 2-4-0 vuled, style slender, 2-lobed ; 

 fruit 2-4 smooth or roughened, 1-seeded nutlets. 



1. V. OFFICINALIS L. European Vervain. Annual; stem 

 erect, slender, nearly or quite smooth, branching, 1-3 ft. high; leaves 

 ovate to obovate in outline, pinnately lobed or divided, narrowed 

 and entire toward the base, pubescent beneath ; petioles margined ; 

 s])ikes several, very slender; flowers small, ])urple, bracts shorter than 

 the calyx. June-September. Tn fields and waste ]^laces ; introduced 

 from Europe. 



2. V. angustifolia Michx. Xakkow-lkaved Vervain. Per- 

 ennial, rougli-hairy ; stem simple, or branched below, from a creejv 

 iiig base, 1-2 ft. liigli ; leaves hinceohite to si):dnlate. obtuse and 

 tootlied at tlie a[tex, tapering to a sessile base; spike i)eduiicled. 



