162 
Spring Flora of Oklahoma 
Stamens 4, all anther-bearing, or 2 sterile, or 2 only. 
Stamens 2 only; corolla rotate, salver-form, tubu¬ 
lar, or none. IV. Veronica. 
Stamens 4, all anther-bearing, ascending under the 
upper lip of the corolla. V. Castilleja. 
I. LIN ARIA (Tourn.) Mill 
Annual or perennial herbs, with erect stems. Leaves 
alternate or opposite, or whorled on the shoots. Flowers 
in terminal racemes, spikes, or panicles. Sepals 5, par¬ 
tially united. Corolla irregular, 2-lipped. Tube spurred 
at the base. Throat partly closed by a convex fold. Sta¬ 
mens 4, didynamous. Capsule ovoid or globose. Seeds 
angled and wrinkled, sometimes winged. 
1. Liliaria canadensis (L.) Dumort. Blue or Wild Toad-Flax. 
Biennial or annual. Flowering steins erect, slender, rarely branched, 
smooth, 12'-24' high. Leaves linear, entire, sessile. Racemes erect, 
slender. Corolla small, blue and white, the spur thread-like, curved, 
longer than the pedicels. Capsule 2-valved. 
In dry soil. April-September. Common. 
II. PENTSTEMON Mitchell. 
Perennial herbs, branching from the base only. Leaves 
opposite. Flowers showy, blue, purple, red, or white, in 
terminal panicles or racemes. Calyx 5-parted. Corolla 
irregular, the tube wide above and narrowed below, 2- 
lipped. Stamens 4 (2 long and 2 short), with a fifth, an¬ 
therless, filament as long as the others, its upper half 
bearded. Capsule ovoid or globose. 
More or less pubescent or glandular, at least the calyx 
and pedicels. 
Corolla long; leaves entire, serrate, or denticu¬ 
late. 
Stem pubescent or puberulent nearly or quite to the 
base. 1. P. hirsutus. 
Only the inflorescence, or pedicels, or calyx pubescent. 
2. P. Digitalis. 
