1082 ACANTHACEAE 



membranous or nearly so, entire. Flowers perfect, in dense spikes : bracts imbricated. 

 Calyx scarious : lobes narrow, entire or toothed near the apex. Corolla white or blue : tube 

 slender, terete : limb 2-lipped : upper lip notched or 2-lobed : lower lip 3-lobed. Stamens 

 2, barely exserted : anthers 2-celled ; sacs equal, parallel, sometimes awn-tipped at the 

 base. Staminodia usually wanting. Ovary 2-celled. Ovules 6-10 in each cavity. Cap- 

 sule narrow, contracted at the base, acute or beaked at the apex. [Elytraria Michx.] 



Bracts with ovate or suborbicular bodies. 



Stems much longer than the leaves : bracts scarious. 1. T. CarolinnwK. 



Stems shorter than the leaves or sometimes slightly surpassing them. 2. T. ajuamosa. 



Bracts with linear or linear-oblong bodies. 3. T. acuminata. 



1. Tubiflora Carolin6nsis (Walt.) J. F. Gmel. Foliage deep green, nearly gla- 

 brous. Leaves basal ; blades oblong, spatulate or elongated linear-spatulate, 0.5-3 dm. 

 long, obtuse; undulate, sessile or short-petioled : stems scape-like, 2-4 dm. tall, virgate, 

 rigid, solitary or clustered, simple, densely scaly : scales appressed, with spreading tips, 

 lanceolate, 6-12 mm. long, acuminate, ciliate : spikes 1-5 cm. long, dense ; bracts with 

 ovl or suborbicular bodies, abruptly pointed : calyx about 8 mm. long ; lobes attenuate, 

 bearded at the tip : corolla white, 7-9 mm. long ;" lobes nearly equal : capsules 4-5 min. 

 long, cylindric, each with a conic tip. [Elytraria virgata Michx. ] 



In low grounds and on river banks, South Carolina to Florida. Summer. A small form occurring 

 in Florida, with linear or narrowly oblanceolate leaf-blades, is T. Carolinensis angwttijolia (Fernald) 

 Small. [Elytraria virgata var. anguttifolia Fernald.] 



2. Tubiflora squamosa (Jacq. ) Kuntze. Foliage pale green. Stems more or less 

 spreading, 1-6 dm. long, commonly branched, clothed with appressed imbricated acute 

 scale-like leaves : normal leaves basal or mainly so : blades oblong, elliptic or narrowly 

 ovate, 4-12 cm. long, entire or sinuate, often slightly pubescent, narrowed into petiole- 

 like bases : spikes 1-3 cm. long : bracts firm, 6-8 mm. long, the body ovate, acute or 

 slightly acuminate : bractlets lanceolate, ciliate : calyx-lobes 5-6 mm. long, ciliate : corolla 

 5-6 mm. long, the lower lip retuse : capsules 6 mm. long. 



In low ground. Texas to Arizona. Also in tropical America and Africa. 



3. Tubiflora acuminata Small. Foliage pale green. Stems ascending or spreading, 

 3-6 cm. long, simple or sparingly branched above, clothed with the appressed acuminate 

 scale-like leaves : normal leaves basal ; blades oblong or oblong-spatulate, 2-6 cm. long, 

 obtuse or rounded, spreading, sparingly pubescent especially on the nerves beneath, sessile 

 or short-petioled : spikes 1-2.5 cm. long: bracts rigid, about 1 cm. long, long-attenuate, 

 woolly above within : bractlets ciliate along the back : calyx-lobes about 7 nun. long, 

 attenuate, barely pubescent at the tip : corolla 5-6 mm. long, the lower lip notched : 

 capsules 4-5 mm. long, each with a conic tip. 



In sandy soil, coast of Texas. 



2. HYGROPHILA R. Br. 



Annual or perennial caulescent herbs, sometimes armed with axillary spines. Leaves 

 opposite : blades entire. Flowers solitary in the axils, or usually clustered. Calyx 

 persistent : lobes 5, narrow, slightly unequal. Corolla commonly white, 2-lipped : tube 

 slightly dilated upward : limb 2-lipped ; upper lip erect, concave, notched or 2-lobed ; 

 lower lip more or less spreading, 2-lobed. Stamens 4, didynamous : filaments slightly 

 dilated at the base : anthers 2-celled : sacs equal, parallel. Staminodium small or obso- 

 lete. Ovary 2-celled. Ovules 2, 4- or more in each cavity. Capsule terete or flattened 

 contrary to the septum. 



1. Hygrophila lacustris ( Schlecht. ) Nees. Perennial, sparingly pubescent. Stem* 

 creeping at the base, the erect or ascending part 3-9 dm. long, 4-angled: leaf-blades nearly 

 linear to narrowly linear-oblanceolate, 5-12 cm. long, rather acuminate, undulate, nar- 

 rowed into dilated bases : cymes few-flowered, nearly sessile in the axils : calyx minutely 

 pubescent ; lobes narrowly linear-subulate, 5-7 mm. long : corolla white, 7 mm. long, 2- 

 lipped ; lobes of the lower lip oblong : capsules cylindric, 7-8 mm. long, nearly terete. 



In swamps and on muddy banks, Florida to Texas and adjacent Mexico. Summer and fall. 



3. CALOPHANES D. Don. 



Perennial herbs or shrubby plants. Leaves opposite : blades entire. Flowers solitary 

 or clustered in the axils. Sepals slender or nearly bristle-like, distinct or united to below 

 the middle. Corolla blue or purple, funnelform : tube slightly curved, more or less dilated 

 upward : limb somewhat 2-lipped : lobes 5, spreading, convolute. Stamens 4, didynamou&, 



