ORDER 89. ACANTHACE^E. 233 



cor. galeate, concave, apex 2-lobed, the lobes broad and spreading, lower 

 lip spreading, trifid, palate not folded. Sta. unequal, ascending beneath 

 the galea. Capsule oblong, compressed, oo-seeded. Herbs with opposite 

 leaves and the flowers in spikes. 



E. officinalis L. Lvs. ovate or oblong, the cauline obtuse, crenate, bracts acute, cut- 

 serrate with cuspidate teeth ; calyx lobes subequal ; corolla light-blue, lower lobes 

 deeply notched. White Mountains, Lake Superior. 26'. Leaves 1 3". 



43. MELAMFYRUM, L. Cow WHEAT. Calyx 4-cleft. Upper lip 

 of the corolla compressed, the margin folded back, lower lip grooved, tri- 

 fid. Caps. 2-celled, oblique, opening laterally. Seeds 1 4, cylindric-ob- 

 long, smooth. Herbs with opposite Ivs. Fls. solitary in the upper axils. 

 1H. pratense, /3. rfmertcdnum (Benth.) Leaves linear-lanceolate, petiolate, glabrous, 

 the upper broader and toothed at base ; Us. axillary, distinct ; cal. teeth slender, half 

 as long as the yellowish corolla, (i) Woods : common. 6 10', branched. Jn. Sept. 



ORDER LXXXIX. ACANTHACE^E. ACANTHADS. 



Herbs or shrubs with opposite, simple leaves and regular, bracted floweis. 

 Calyx 5-parted, equal or unequal, imbricated hi the bud. Corolla 5-merous, 

 tubular below, limb more or less bilabiate, convolute in bud. Stamens 

 didynamous or diandrous, inserted on the tube of the corolla. Fruit a 

 2-celled, 4-12-seeded capsule. Seeds supported by hooks or cup-shaped 

 processes of the placentae, exalbuminous. 



5 Seeds destitute of hooked supports. . .(a) 



a Corolla regular. Seeds few, resting on little cups. Vines THUNBBRGIA. 1 



a Corolla bilabiate. Seeds many, with no supports ELYTBARIA. 2 



S Seeds resting on hooks proceeding from the placentae.. ..(6) 



b Corolla funnel-form, subregular. Stamens 4, unequal RUEI.LI A. S 



b Corolla bilabiate, ringent. Stamens 4. Pod terete HYGROFHILA. 4 



6 Corolla labiate, the upper lip wanting. Stamens 4. t Rare ACANTHUS mollis 



b Corolla bilabiate. Stamens 2. c Corolla inverted, upper lip 3-toothed DICLIPTERA. 5 



c Corolla straight, lower lip 3-lobed Di ANTHER A. 6 



c Corolla straight, lower lip 3-parted CYRTANDRA. 7 



1. THUNB^RGIA, L. Calyx short, toothed or truncate, with 2 large 

 bractlets at base. Cor. funnel-bell-form, limb 5-lobed, nearly regular. Sta. 

 4, unequal, included. Caps, beaked, 3-4-seeded. 5 ^ Fls. showy, axillary. 

 T. ALATA. A climbing vine, silky-hairy, with cordate-sagittate Iva. on winged pet. ; 



fls. H' deep and broad, purple, with a yellow, buff, orange or white border. E. Africa. 



2. ELYTRARIA, Vahl. Calyx with 4 or 5 unequal segments. Cor 

 bilabiate, lower lip of 3 bifid segments. Sta. 2 fertile, 2 sterile, included. 

 Caps. 8-seeded. Herbs acaulescent, with (oblong) leaves at base and clasp 

 ing bracts on the scapes, and the small flowers in a terminal spike. 



K. virguta MX. Scapes several, glabrous, covered with the bracts, which are ovate, 

 cuspidate, ciliate, the upper subtending the white flowers ; calyx with 2 linear bract 

 lets at base, ciliate. y Wet plains, S. Car. to Fla. If. August. 



3. RUELLIA, L. Calyx 5-parted into slender segments. Cor. funnel- 

 form, limb spreading, subequally 5-lobed. Sta. 4, included, didynamous 



