LAMIACEAE. 249 



long: nutlets about 1.5 mm. loug. — Commou, near dwellings, in tMckets and 

 on hillsides. Nat. of Eu. — Spr. — Ground-ivy. Gill-over-the-ground. 



10. PRUNELLA L. Perennial erect or diffuse herbs. Leaf -blades toothed 

 or laciniate. Flowers mostly in compact panicles. Calyx 2-lipped: upper 

 lip with 3 broad lobes: lower lip with 2 narrow lobes. Corolla 2-lipped: 

 upper lip arched: lower lip with the broad middle lobe generally toothed. 

 Filaments relatively long, 2 of them forked at the apex. — Self-heal. 



Leaf-bkules entire or shallowly toothed: calyx over 10 mm. long; lobes of the 

 lower lip subulate. 1. 1'. vulgaris. 



Leaf-blades, at least the upper ones, pinnatifld : calyx less than 10 



mm. long ; lobes of the lower lip lanceolate. 2. P. laciniata. 



1. P. vulgaris L. Stems 0..5-4 dm. long: leaf-blades ovate, oblong, or lanceo- 

 late, 2-7.5 cm. long, undulate: bracts mostly reniform: calyx 6-8 mm. long; 

 lobes of the upper lip mueronate : corolla purj^le or white, mainly 14-18 mm. 

 long : nutlets about 2 mm. long. — Common, in fields, thickets and waste places. 

 Nat. of Eu. — Spr. and sum. — Heal-all. 



2. P. laciniata L. Plants similar to P. vulgaris in habit, but often hoary- 

 pubescent: blades of the stem-leaves more or less pinnatifld: corolla white 

 or pale. — M. S. Occasional, in flelds and lawns. Nat. of Eu. — Sum. 



11. DE.ACOCEPHALUM [Tourn.] L. Perennial, erect or reclining 

 herbs. Leaf-blades typically narrow, usually toothed, at least near the apex. 

 Flowers in spike-like racemes. Calyx essentially regular: lobes 5, shorter than 

 the tube. Corolla 2-lipped: upper lip arched, entire: lower lip 3-lobed. Sta- 

 mens 4: filaments elongate, one pair at least glabrous. [Physostegia Benth.] 

 — Sum. — False-dragon-head. 



Leaf-blades entire or bluntly toothed: stem naked above: lateral lobes of the lower 

 corolla-lip often entire. 1. D. denticulatum. 



Leaf-blades sharply toothed : stem leafy above : lateral lobes of 



the lower corolla-lip often toothed. 2. D. virginianum. 



1. D. denticulatum Ait. Stems 3-9 dm. long: leaves few; blades spatu- 

 late to oblong, 2-14 cm. long, thick, repand-crenate, mostly obtuse: calyx-lobes 

 deltoid : corolla 20-25 mm. long : nutlets about 2 mm. long. — Susquehanna 

 valley. Occasional, on islands and shores. — Schists. 



2. D. virginianum L. Stems 3-15 dm. long: leaves many; blades narrowly 

 oblong to linear-oblong or oblong-lanceolate, 3-12 cm. long, thickish, saliently 

 serrate or incit^^ed-serrate, mostly acuminate or acute: calj'x-lobes lanceolate to 

 ovate-lanceolate: corolla 25-30 mm. long: nutlets about 3 mm. long. — Sus- 

 quehanna valley. Frequent, on low islands and shores. — Schists. 



12. LAMIUM L. Annual, biennial (ours), or perennial, diffuse herbs. 

 Leaf-blades broad, toothed or incised. Flowers in axillary cymes. Calyx 

 somewhat irregular: lobes 5, the upper ones usually the larger. Corolla blue 

 or white, 2-lipped: upper lip entire or merely notched: lower lip 3-lobed, 

 the middle lobe with a dilated blade, the lateral lobes with slender tips. Sta- 

 mens 4 : filaments pubescent. — Dead-nettle. 



Leaf-blades sessile or partly clasping on the upper part of the stem : corolla abruptly 

 bent at the throat ; lateral lobes of the lower lip rounded. 1. L. amplexicaule. 



Leaf-blades petioled on the upper part of the stem : corolla 



curved at the throat; lateral lobes of the lower lip lobed. 2. L. puruurcum. 



1. L. amplexicaule L. Stems and branches decumbent, sparingly retrorse- 

 pubescent: leaf-blades suborbicular to orbicular-reniform, 1-3.5 cm. wide, 



