38 PONTEDERIACEAE. 



very slender, 4-30 cm. tall, 5-6-ridged: heads spheroidal, 3-5 mm. thick; 

 bracts of the involucre obtuse: bractlets, sepals, and petals glabrous. — Ever- 

 glades and low pinelands. 



Fahilt 3. COMMELINACEAE. Spiderwort Family. 



Annual or perennial caulescent succulent herbs. Leaves alternate, 

 sheathing at the base. Flowers i^erfect, the mostly umbel-like cymes 

 involucrate. Calyx of 3 persistent herbaceous sepals. Corolla of 3 equal 

 or unecjual delicate petals. Androecium of 5-6 stamens, sometimes 2 or 3 

 mere staminodia. Gynoecium 2-3-carpellary. Styles i;nited. Fruit a 

 loculicidally 2-3-valved capsule. 



Petals all alike: polleniferous stamens 6. 1. Rhaeo. 



Petals unequal in size and shape : polleniferous stamens 3 or 2. 2. Commblina. 



1. RHAEO Hauce. Leaves erect or nearly so, stiff, crowded: blades con- 

 tracted above the sheathing base. Cymes congested, borne in an involucre of 

 imbricate boat-like bracts. Petals equal, not clawed. Capsule sessile. 



1. R. discolor (L'Her.) Hanee. Leaves 2-4 dm. tall; blades very thick, 

 broadly linear, acute, often purple, especially so beneath: flower-stalks clustered: 

 spathes 3-4 em. long: petals white or blue, 5-8 mm. long: capsules 4-5 mm. 

 long. — Pinelands and cultivated grounds. Nat. of Mex., and cultivated. — 

 (Bah., Cuba. Ant.) 



2. COMMELINA [Plum.] L. Leaf-blades spreading, relatively short. 

 Cymes borne in a specialized folded involucre. Perianth irregular. Stamens 

 3 or rarely 2. Capsules hidden in the spathe. — Day-flower. Dew-flower. 



Leaf-blades linear to narrowly linear-lanceolate : leaf-sheaths glabrous or nearly so. 

 Rootstocks and roots abbreviated, the latter slender-fusi- 

 form : internodes below the sheath pubescent or scabrous. 1. C. hamipila. 

 Rootstocks and roots elongate, the latter cord-like : inter- 

 nodes below the sheaths glabrous. 2. C. angustifolia. 

 Leaf-blades lanceolate, elliptic or oblong-lanceolate : leaf-sheath 



hirsute. 3. C. elegans. 



1. C. hamipila Wright. Stem or brauches 1-4 dm. long, from a cluster of 

 fusiform roots: leaf-blades linear or narrowly linear-lanceolate, attenuate: 

 spathe about 2 cm. long, acuminate: capsules about 5 mm. long. [C. Stving- 

 leana Nash.] — Pinelands. — F. K. (Cuha.) 



2. C. angustifolia Michx. Stem or branches 2-8 dm. long, from cord-like 

 roots: leaf-blades linear, sometimes narrowly so, flat, attenuate: spathes 2-2.5 

 cm. long, acute or acuminate: capsules 4-5 mm. long. — Pinelands. F. K. 



3. C. elegans IT. B. K. Stem and branches 2-9 dm. long: leaf -blades lanceo- 

 late to elliptic or oblong-lanceolate, 4-10 cm. long: spathes 1.5-2 cm. long, 

 acute: capsules about 4 mm. long. — Coastal sand-dunes. — (Ber., Bah., Ant.) 



Family 4. PONTEDERIACEAE. Pickerel-weed Family. 



Bog or aquatic herbs with rootstocks. Leaves alternate: blades 

 dilated, naiTOw, or mere phyllodia. Flowers 1 or several from a bract- 

 like spathe. Calyx and corolla of rather similar partially united members. 

 Androecium of 3-6 stamens: filaments unequally adnate to the perianth 

 tube. Gynoecium 3-carpellary, but sometimes with a 1-oelled ovary. 

 Fruit a 1-seeded utricle or a many-seeded eai)sule. 



