9(3). Leaves serrate-dentate or shallowly incised 6. V. Macdougalii.. 



9. Leaves deeply incised-dentate to pinnatifid or 3-cleft (10) 



10(9). Spikes conspicuously bracteose with somewhat foliaceous bractlets (at 

 least at the base of the spike) 7. V. bracteata. 



10. Spikes not conspicuously bracteose; bractlets not foliaceous (11) 



11(10). Corolla mostly blue 8. V. Runyonii. 



11. Corolla mostly rose-color 8. V. Runyonii f. rosiflora. 



1. Verbena bonariensis L. South American vervain. 



Stiffly erect, 1 m. or more tall, somewhat scabrous-pubescent; leaves sessile, 

 subcordate and semiamplexicaul at base, lanceolate or oblong, sharply serrate, 

 rugose and hirtellous above, spreading-pubescent beneath; spikes compact, mostly 

 short, usually sessile and crowded in dense fasciculate cymes, not elongating; 

 bractlets lanceolate-acuminate, barely equaling or slightly surpassing the calyx, 

 pubescent; calyx 3 mm. long, pubescent, the acute lobes with short subulate tips; 

 corolla blue to violet or purple, the tube scarcely twice as long as the calyx, 

 pubescent outside, limb inconspicuous. 



Sandy loam, ditch banks, wet or moist flatlands and along rice field fences, 

 in Okla. (McCurtain Co.) and in e. Tex. from Red River to Jefferson cos., Apr.— 

 June; nat. of Braz., Parag., Urug. and Arg.; introd. in W.L, s. U.S. and elsewhere. 



2. Verbena brasiliensis Veil. Brazilian vervain. 



Stems stout, to 25 dm. tall, acutely tetragonal, practically glabrous below, 

 somewhat scabrous-pubescent above, slightly contracted at nodes; leaves elliptic 

 or lanceolate, tapering into a cuneate subsessile or petiolar base, sharply serrate 

 or incised (at least above the middle), strigillose and somewhat pustulate above 

 with impressed venation, sparsely pubescent beneath; spike compact, mostly 

 short, not much elongating, usually sessile in open cymes, numerous but not 

 crowded; bractlets scarcely as long as the calyx, lanceolate-subulate, ciliate; calyx 

 2.5-3.5 mm. long or more, somewhat appressed-pubescent, the acute lobes with 

 short subulate tips; corolla purple or lilac, the tube a little longer than the calyx, 

 pubescent outside, the limb 2.5 mm. wide, inconspicuous. 



Waste places, dry sandy soil, coastal prairies, in swamps and marshes about 

 lakes and on seepy banks of ponds, in Okla. (Woodward Co.) and mainly in s.e. 

 Tex., May-Oct., introd.; nat. to most of S.A.; naturalized from Va. to Fla. and 

 Gulf Coast, Ore., Calif., Jam., S. Afr. and elsewhere. 



3. Verbena scabra Vahl. Sandpaper vervain. Fig. 654. 



Stems to 1 m. tall, erect, solitary, simple or branched, hispidulous; leaves ovate, 

 3-13 cm. long, to 5 cm. wide, petiolate, acute or obtusish, serrate-dentate, very 

 rough and usually strigillose above, less scabrous and paler beneath, hispidulous 

 on the venation; spikes paniculate, slender, pedunculate, closely many-flowered; 

 bractlets ovate-acuminate, half as long as the calyx, hispidulous; calyx 2.5-3 mm. 

 long, ovoid, hispidulous, diverging from the rachis by 45° or more, the unequal 

 lobes acutely connivent; corolla blue, the tube about equaling the calyx, limb 2 

 mm. wide, lobes obtuse; stigmatic surface midway between 2 almost equal ob- 

 tusish sterile style lobes. 



Mostly rich soil of low ground, marshes, swamps and edges of lakes and 

 streams, Okla. (Cherokee Co.) and throughout most of Tex. except Plains Coun- 

 try, N. M. (Eddy Co.) and Ariz. (Gila, Pinal, Santa Cruz and Pima cos.), Mar.- 

 Dec; N.C. to Fla. and W.L, w. to Ariz., Calif, and n. Mex. 



Forma angustifolia Moldenke diff'ers in having elliptic-lanceolate leaves only to 

 2 cm. wide; known only from Burnet Co., Tex. 



1397 



