LAMIACEAE. 253 



stout, nearly equally 5-lobed. Corolla 2-lipped: upper lip broad, slightly 

 lobed: lower lip with 3 rather broad lobes. Stamens 4. Stigmas short. 



1. O. vulgare L. Stems mostly simple below, sparingly branched above, 

 villous-Mrsute : leaf -blades ovate, mostly 1.5-2.5 cm. long, shallowly toothed: 

 calyx 2-2.5 mm. long; lobes ovate, longer than the tube: corolla purple or 

 rarely white, 6-7 mm. long; lobes of the upper lip rounded, the lateral lobes 

 of the lower lip broadly ovate : nutlets less than 1 mm. long. M. S. Fre- 

 quent, on roadsides and in fields. Nat. of Eu. Sum. WILD-MARJORAM. 



22. THYMUS [Tourn.] L. Perennial depressed or creeping herbs. Leaf- 

 blades short, mostly entire. Flowers in axillary cymes or raceme-like panicles. 

 Calyx 2-lipped, the upper lip with 3 short lobes, the lower lip with 2 longer 

 lobes. Corolla 2-lipped: upper lip erect: lower lip 3-lobed, the middle lobe 

 scarcely larger than the lateral ones. Stamens 4. Stigmas long. THYME. 



1. T. Serpyllum L. Plants fragrant, forming depressed mats: leaf -blades 

 oblong to oval or ovate, 3-10 mm. long: calyx becoming 3.5-4 mm. long; lobes 

 of the lower lip about as long as the tube: corolla purplish, about as long as 

 the calyx : nutlets less than 1 mm. long. M. Occasional on roadsides and in 

 fields. Nat. of Eu. Sum. CREEPING-THYME. 



23. KOELLIA Moench. Perennial erect herbs. Leaf-blades entire or 

 shallowly toothed. Flowers in dense axillary and terminal cymes. Calyx nearly 

 regular, the lobes short or elongate. Corolla 2-lipped: upper lip erect: lower 

 lip 3-lobed, the middle lobe larger than the lateral ones. Stamens 4. Sum. 

 MOUNTAIN-MINT. HORSE-MINT. BASIL. 



Calyx not 2-lipped ; lobes equal or nearly so. 



Calyx-lobes triangular or ovate-triangular. 1. K. vtrgimana. 



Calyx-lobes subulate to lanceolate. 



Leaf-blades or most of them over 3 times as long as 



broad. 



Leaves with strictly entire blades. 2. K. flexuosa. 



Leaves, or the larger ones, with toothed blades. 

 Flower-clusters 1-2 cm. broad at maturity, com- 

 pact : calyx-lobes not bristly. 3. K. verticillata. 

 Flower-clusters 2-3 cm. broad at maturity, not 



crowded : calyx-lobes bristly. 4. K. clinopodioides. 



Leaf-blades or most of them less than 3 times as long 



as broad. 5. K. mutica. 



Calyx manifestly 2-lipped by the partial union of the 3 



upper lobes. 6. K. incana. 



1. K. virginiana (L.) Britton. Stems 4-9 dm. tall, minutely pubescent: leaf- 

 blades lanceolate to linear-lanceolate, 2-5 cm. long, mostly entire: calyx 3.5-4 

 mm. long; lobes triangular to ovate-triangular: corolla 6-7 mm. long; upper 

 lip notched; middle lobe of the lower lip slightly narrower than the lateral 

 ones. Common, in thickets. . 



2. K. flexuosa (Walt.) MacM. Stems 3-8 dm.- tall, glabrous: leaf -blades 

 narrowly linear to linear-filiform, 1-4 cm. long, entire: calyx about 3.5 mm. 

 long; lobes lanceolate to triangular-lanceolate: corolla 6-7 mm. long; upper 

 lip minutely notched; middle lobe of the lower lip much narrower than the 

 lateral ones. Common, in dry soil, fields and thickets. 



4. K. clinopodioides (T. & G.) Kuntze. Stems 4-12 dm. tall, softly-pubescent: 

 leaf-blades lanceolate to almost linear, 2-6 em. long, remotely or shallowly 

 serrate: calyx 4-5 mm. long; lobes subulate-lanceolate: corolla 6-7 mm. long, 

 or rarely longer. Susquehanna valley. Occasional, in open thickets and 

 woods. Schists. 



4. K. clinopodioides (T. & G.) Kuntze. Stems 4-12 dm. tall, softly-pubescent 

 leaf -blades lanceolate, narrowly oblong, or elliptic, 2-8 cm. long, more or less 



