ORDEK 89. ACANTHACE^E. 233 



cor. galeate, concave, apex 2-lobed, the lobes broad aud 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. 



B. officlnalls L. Lvs. ovate or oblong, the canline obtuse, crenate, bracts acute, cut- 

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

 deeply notched. White Mountains, Lake Superior. 26'. Leaves 13". 



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

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

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

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



in. prateiise, p. ~imericdnum (Benth.) Leaves linear-lanceolate, petiolate, glabrous, 

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

 as long as the yellowish corolla. 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 in 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. 



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



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



a Corolla bilabiate. Seeds many, with no support! ELYTRARIA. 2 



I Seeds resting on hooks proceeding from the placentae.. ..(A) 



b Corolla funnel-form, subregular. Stamens 4, unequal RUELLIA. 3 



6 Corolla bilabiate, ringent. Stamens 4. Pod terete HTGROPHILA. 4 



b Corolla labiate, the upper lip wanting. Stamens 4. t Bare ACANTHUS mollis 



It Corolla bilabiate. Stamens 2. c Coroila inverted, upper lip 3-toothed DICMPTERA. 5 



c Corolla straight, lower lip 3-lobed DIANTHKUA. 6 



Corolla straight, lover lip 3-parted CYRTANDRA. 7 



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

 bractlets at base. Cor. funnel-be'll-form, limb 5-lobed, nearly regular. Sta. 

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

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



fls. 1|' deep and broad, purple, with a yellow, buff, orange or white border. E. Africa. 



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

 bilabiate, lower lip of 8 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. 



E. virgata MX. Scapes several, glabrous, covered with the bracts, which are ovate, 

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

 lets at base, ciliate. if. 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 



