LAMIACEAE 1019 
or oblong-lanceolate, 4-9 cm. long, acute, sharply serrate, mostly rounded at the base, 
tomentulose or hirsute beneath with spreading hairs on the larger veins: panicles narrow, 
dense, sometimes elongated: bract mostly shorter than the calyx, acuminate: calyx 5-6 
mm. long, often purple; lobes various, the upper acute, the lower ones lanceolate-sub- 
ulate: corolla pinkish purple, 8-12 mm. long, tomentulose and glandular without. 
In low grounds and thickets, Ontario to British Columbia, Arkansas and California. Summer. 
2. MELOSMON Raf. 
Perennial or annual diffuse herbs, with glabrous or finely pubescent foliage. Leaves 
opposite: blades incised or parted. Flowers solitary in the axils of the leaf-like bracts. 
Calyx pedicelled: tube 10-ribbed, very short: lobes 5, equal or essentially so. Corolla 
white, blue or lilac, very irregular: upper lip relatively small: lower lip with 2 lateral 
lobes and a much longer middle lobe. Stamens 4, exserted as in Teucrium. Nutlets 
smooth or ribbed, sometimes corky thickened. 
Leaf-blades incised, the tooth-like lobes blunt. 1. M. Cubense. 
Leaf-blades parted, the divisions narrow and mostly acute. 
Corolla between 1 and 1.5 em. long: leaves not approximate. 2. M. laevigatum. 
Corolla between 1.5-2 cm. long: leaves approximate and imbricated. 3. M. laciniatum. 
1. Melosmon Cubénse (L.) Small. Stems often branched at the base, the branches 
erect or ascending, 2-5 dm. tall, commonly branched above : leaf-blades spatulate to ovate 
in outline, cuneate at the base, 1-3 cm. long, incised, the tooth-like lobes mostly entire : 
bracts similar to the leaves: pedicels 2-5 mm. long: calyx 4-5.5 mm. long ; lobes lanceo- 
late to linear-lanceolate, acuminate, several times longer than the tube, finely pubescent : 
corolla bluish white, 11-14 mm. long : nutlets fully 2 mm. long, irregularly roughened. 
In sandy soil, Texas and Mexico. Also in the West Indies. 
2. Melosmon laevigàtum (Vahl) Small. Stems branched at the base, the branches 
ascending or spreading, 1-6 dm. long, simple or irregularly branched, not ieri leafy : 
leaf-blades 1-4 cm. long, laciniately 3-5-lobed, the lobes linear, entire or toothed, acute: 
bracts leafy: pedicels slender, 3-6 mm. long: calyx 7-8 mm. long; lobes linear-lanceo- 
late, acute, several times longer than the tube, glabrous or nearly so: corolla white or 
bluish, 1-1.5 em. long, the upper lobes 3-4 mm. long, acutish, the lower lip nearly 1 em. 
long, sparingly villous without, its middle lobe pendant, oblong or elliptic : nutlets 2 mm. 
long, longitudinally ribbed and pitted between the ribs. [Teucrium laevigatum Vahl. ] 
Insandy soil, Texas. Alsoin South America. Spring. yi 
3. Melosmon lacíniàtum (Torr. ) Small. Stems usually branched at the base, the 
branches 5-15 cm. long, ascending or spreading, densely leafy, except near the base : leaf- 
blades pinnately 3-7-parted, 1-3 cm. long, the segments narrowly linear, entire, incised or 
lobed : bracts leafy: pedicels 2-6 mm. long: calyx 10-12 mm. long; tube turbinate, 
strongly ribbed ; lobes linear-subulate, acuminate, several times longer than the tube: 
corolla pale blue or lilac, sparingly pubescent without, 1.5-2 cm. long, the upper lobes 
ovate, the lower lip much surpassing the calyx, its middle lobe oblong-spatulate, concave : 
nutlets 2.5 mm. long, reticulated and granular. [Teucrium laciniatum Torr. ] 
On plains, Colorado to Texas and Arizona. Spring. 
3. ISÁNTHUS Michx. 
Annual herbs, with viscid-pubescent foliage and branching stems. Leaves opposite : 
blades narrow, entire or sparingly toothed. Flowers in axillary cymes. Calyx campanu- 
late: tube 10-ribbed : lobes 5, nearly equal, narrow. Corolla blue, nearly regular: lobes 
broadened upward, spreading. Stamens 4, slightly didynamous, surpassing the corolla- 
tube, thus slightly exserted : anthers with diverging sacs at maturity. Nutlets reticulated. 
1. Isanthus brachiatus (L.) B.S.P. Annual, minutely viscid-pubescent. Stems 
1-4 dm. tall, branching : leaf-blades elliptic or linear-elliptic, 1-4 cm. long, acute at both 
ends, entire or rarely toothed, 3-nerved, short-petioled : peduncles axillary, 1-3-flowered : 
calyx green or purple; tube campanulate, 2-5 mm. long, ridged; lobes lanceolate or 
triangular-lanceolate, as long as the tube or longer: corolla blue, 5-8 mm. long: nutlets 
2-2.5 mm. long, strongly reticulated. [J. coeruleus Michx.] 
In dry soil, Quebec and Ontario to Minnesota, Georgia and Texas. Summer and fall. 
4. TRICHOSTEMA L. 
Annual or perennial herbs or shrubby plants, with glabrous or viscid foliage and 
branching stems. Leaves opposite: blades rather narrow, entire or merely repand. 
