COMMELINACEAE 237 



bases. Flowers perfect, solitary or several in variously suppressed cymes, aris- 

 ing from a spathe or involucre of often leaf-like bracts. Perianth in 2 series. 

 Calyx of 3 distinct mostly persistent herbaceous sepals. Corolla often showy, 

 regular or irregular, of 3 early withering or fugacious petals. Androecium of 

 5-6 hypogynous stamens, all of these perfect, or 2-3 sterile. Filaments slender. 

 Anther-sacs mostly opening lengthwise. Gynoecium of 2-3 united carpels. 

 Ovary superior, 2-3-celled. Styles united. Stigma sometimes obscurely 2-3- 

 lobed. Ovules solitary or several in each cavity, orthotropous. Fruit a loculici- 

 dally 2-3-valved capsule. Seeds sometimes suppressed in one cavity. Embryo 

 pulley-shaped in the copious endosperm opposite the hilum. 



Petals alike in shape : perfect stamens 6 or rarely 5. 



Cymes elongated, scorpioid. 1. TINANTIA. 



Cymes or cymules umbel-like or clustered. 



Cymes or cymules subtended by small or minute bracts very unlike the 



leaves. 



Inflorescence simple : filaments pubescent. 2. CUTHBERTIA. 



Inflorescence dichotomously compound : filaments glabrous. 3. TRADESCANTELLA. 



Cymes subtended by an involucre of 1-3 bracts similar to the leaves. 

 Petals broad at the 



ic base and distinct : filaments free. 4. TRADESCANTIA. 



Petals with claws and coherent into a tube : filaments adnate to the 



petals. 5. TRELEASEA. 



Petals unequal in size and shape : perfect stamens 3 or rarely 2. 6. COMMELINA. 



1. TINANTIA Scheidw. 



Perennial herbs, with upright steins. Leaves alternate : blades flat, often quite 

 ample. Peduncles terminal or sometimes in the upper axils. Involucre of leaf -like bracts. 

 Cymes elongated, scorpioid. Sepals 3, nearly equal. Petals 3, nearly equal, showy. 

 Stamens 6, all fertile : filaments filiform, pubescent. Capsule loculicidally 3-valved. 

 Seeds in one row : testa rough or rugose. 



1. Tinantia andmala (Torr. ) Clarke. Stems weak, solitary or tufted, 2-7 dm. tall, 

 glabrous : leaf-blades linear-spatulate below and narrowed into slender petioles, lan- 

 ceolate or ovate-lanceolate above, 5-12 cm. long, acute or acuminate, glaucescent beneath, 

 cordate, clasping at the base : pedicels 2-5 mm. long : sepals oblong or oblong-lanceolate, 

 10-12 mm. long, acute : petals deep blue, obovate-elliptic, or obovate, longer than the 

 sepals : filaments pubescent above : capsule oblong-oval, 6 mm. long. 



In rich soil and woods, Texas. Spring and summer. 



2. CUTHBERTIA Small. 



Perennial herbs, with mostly tufted stems. Leaves alternate : blades very narrow and 

 elongated. Cymes umbel-like, solitary at the ends of long peduncles, and subtended by 

 very small bracts wholly unlike the leaves. Sepals 3. Petals 3, reddish, pink or rose- 

 purple, distinct. Stamens 6 : filaments pubescent. Capsule loculicidally 3-valved. Seed 

 with a rough testa. 



Leaf-blades mostly 1-3 mm. broad : corollas 1-2 cm. broad : capsules subglobose. 1. C. graminea. 



Leaf-blades mostly 5-8 mm. broad : corollas 2-2.5 cm. broad : capsules obovoid. 2. C. rosea. 



1. Cuthbertia graminea Small. Stems erect, 0.5-2* dm. tall, densely tufted, 

 sometimes 100 or more together, commonly simple, barely zigzag. Leaves quite numer- 

 ous ; blades narrowly linear or linear-filiform, 1-1.5 dm. long, or shorter above, mostly 

 1-3 mm. broad, acute, mostly erect ; sheaths ciliate : peduncles sometimes overtopping the 

 leaves : cymes 3-15-flowered, simple : pedicels slightly thickened at the apex, becoming 

 about 10 mm. long : sepals oblong-ovate or ovate, 4-5 mm. long, glabrous : corollas pink 

 or rose-colored, 1-2 cm. broad : capsules subglobose, about 3 mm. in diameter. 



On sand hills or in sandy woods, Maryland and Missouri to Florida and Texas. Spring and summer 



2. Cuthbertia rosea (Vent. ) Small. Stems erect or ascending, 2-6 dm. tall, sparingly 

 tufted, or solitary, zigzag. Leaves relatively few ; blades linear, 1-3 dm. long, or shorter 

 above, mostly 5-8 mm. broad, acute, spreading at maturity ; sheaths ciliate : peduncles 

 5-18 cm. long : cymes 3-10-flowered : pedicels 15 mm. long, abruptly thickened at the 

 apex: sepals ovate, becoming 4-5 mm. long, glabrous: corollas 2-2.5 cm. broad, rose- 

 purple : capsules obovoid, about 3 mm. long. [Tradescantia rosea Vent.] 



In sandy oak woods or pine lands, North Carolina to Georgia and Florida. Spring and summer. 



3. TRADESCANTELLA Small. 



Perennial herbs, with spreading or creeping stems. Leaves alternate : blades rel- 

 atively short and broad. Cymes dichotomous, the cymules subtended by very small 



