160 ELEMENTS OF BOTANY. 



IV. KNEIFFIA. 



Annual, perennial, or sometimes shrubby ; leaves alternate, 

 usually narrow ; flowers in terminal spikes or racemes, yel- 

 low, diurnal ; calyx tube prolonged beyond the ovary, the 

 lobes often united at the apex, finally becoming reflexed; 

 petals 4 ; stamens 8, the alternate ones longer ; style slen- 

 der, stigma 4-parted; capsule sessile or peduncled, clavate, 

 4-angled, seeds many. 



1. K. LINEARIS (Michx.) Spach. Narrow-leaved Primrose. 

 Biennial or perennial; stem erect or ascending, slender, simple or 

 branched, smooth or pubescent, 12-18 in. high; lower leaves ob- 

 ovate, the upper linear or linear-spatulate, entire or slightly toothed ; 

 racemes terminal, short, leafy, many-flowered; flowers yellow, l-l^^ 

 in. broad ; calyx pubescent, the tube | in. long; petals obcordate ; 

 capsule narrowly obovate, prominently 4-winged with 4 intermediate 

 ribs, shorter than the pedicel. April-,! une. On dry, sandy soil. 



2. K. FRUTicosA (L.) Raim. Sundrops. Perennial; stem 

 erect, simple or branched, more or less pubescent ; leaves lanceolate, 

 sessile or short-petioled, wavy-denticulate on the margins ; racemes 

 terminal, finally much elongated ; flowers yellow, diurnal, li-2 in. 

 broad ; calyx tube longer than the ovary ; petals obcordate ; capsule 

 oblong-clavate, sessile or nearly so, prominently 4-winged with inter- 

 mediate ribs, longer than the pedicel. June-September. In old 

 fields. 



V. GAURA. 



Annual, biennial or perennial herbs, sometimes woody at 

 the base ; leaves alternate, sessile ; flowers in terminal spikes 

 or racemes ; calyx tube slender, prolonged beyond the ovary, 

 4-lobed, the lobes reflexed ; petals 4, long-clawed, unequal ; 

 stamens 6-8, usually turned to one side ; style declined, 

 stigmas 4-lobed, ovary 3-4-celled ; fruit a 3-4-angled cap- 

 sule, mostly 1-celled, 3-4-seeded. 



1. G. BIENNIS L. Biennial Gaura. Biennial; stems erect, 

 widely branched,, soft-pubescent, 3-8 ft. high ; leaves oblong-lanceo- 

 late or elliptical, acuminate, wavy-denticulate, pubescent or becom- 

 ing smooth above ; flowers sessile in long-peduncled spikes ; petals 

 white, fading to pink ; fruit sessile, narrowly ovoid, obtusely 4-angled. 

 pubescent. June-September. On dry soil, more coiiunon north- 

 ward. 



