VERBENACEAE. 309 



Family 91. VERBENACEAE. Vervain Family. 



Herbs or shrubs with usually opposite or verticillate 

 leaves, and perfect more or less irregular flowers in ter- 

 minal or axillary spikes, racemes or panicles. Calyx 

 usually 4-5-lobed or 4-5-cleft, persistent. Corolla regu- 

 lar or 2-lipped, the tube usually cylindric, the limb 4-5- 

 cleft. Stamens usually 4, didynamous, rarely only 2, 

 inserted on the corolla and alternate with its lobes; 

 anthers 2-celled, the sacs longitudinally dehiscent. 

 Ovary superior, 2-4-celled, composed of 2 carpels with 2 

 ovules; style simple; stigmas 1 or 2. Fruit dry, sepa- 

 rating at maturity into 2 or 4 nutlets, or a drupe con- 

 taining the 2-4 nutlets. 



Corolla 5-lobed, regular or nearly so; nutlets 4. 1. Verbena. 



Corolla 4-lobed, 2-lipped; nutlets 2. 2. Lippia. 



1. VERBENA L. 



Herbs, mostly with opposite leaves and variously 

 colored bracted flowers in terminal solitary, corymbose 

 or panicled spikes. Calyx usually tubular, 5-angled, 

 more or less unequally 5-toothed. Corolla salver-shaped 

 or funnelform, its limb spreading, 5-lobed and slightly 

 2-lipped or regular. Stamens 4, didynamous or rarely 

 only 2, included; connective of anthers unappendaged or 

 sometimes provided with a gland. Ovary 4-celled; 

 ovules 1 in each cell; style usually stout, 2-lobed, only 1 

 of the lobes stigmatic. Fruit dry, mostly enclosed by 

 the calyx, at length separating into 4 1 -seeded, linear or 

 linear-oblong, smooth or rough nutlets. 



Bracts shorter than the flowers. 



Calyx scabrous, scarcely 2 mm. long. 1. V. urticifolia. 



Calyx glandular-villous, 4 mm. long. 2. V. prostrata. 



Bracts longer than the flowers. 3. V. hracteosa. 



1. V. urticifolia L. Stems minutely hirsute-pubescent to almost 

 glabrous, erect, 10-16 dm. high; leaves thin, petioled, ovate to 

 oblong-lanceolate, acuminate or acute, evenly or doubly serrate; 

 spikes slender-filiform, panicled; bracts ovate, acuminate, shorter 

 than the calyx; corolla 2-4 mm. long, white or purplish. 



Occasional in marshes. 



