3. Commelina diffusa Burm. f. 



Plant annual, with a fibrous root system; stems at first erect, later becoming 

 decumbent because of profuse branching and layering, rarely more than 1.5 mm. 

 in diameter, the larger internodes to 10 cm. long; leaves broadly lanceolate, 

 glabrous beneath, glabrous to slightly scabrous above, 3.5-11 cm. long, 9-22 mm. 

 wide; leaf sheaths 5-10 mm. long, the throat usually lined with long white hairs or 

 sometimes with only short hairs; spathe stalk 1-2 cm. long; spathe glabrous, open 

 across top, tapering to a slightly attenuated tip at the abaxial end and open down 

 the adaxial side to the point of attachment to the stalk, the bottom usually de- 

 curved at the tip. 



In floodplain woods, stream beds and wet clays about ponds in s.e. Okla. 

 (LeFlore Co.) and e. and s. Tex., Apr.-Nov.; in s.e. U.S., w. to Tex., Okla. and 

 Kan. 



2. Tradescantia L. Spider lily. Spiderwort 



Subsucculent perennial herbs; stem erect to trailing, herbaceous, frequently 

 producing subterranean stolons; leaves alternate, sessile, linear to oblong-elliptic 

 (in our species), the blade basally produced into a perfoliate sheath; inflorescence 

 an umbellate dichotomous helicoid cyme, terminal or lateral, subtended by 2 or 

 infrequently 3 subequal or unequal foliaceous or rarely scarious bracts; pedicels 

 subtended by solitary or paired hyaline or slightly foliaceous bracteoles; sepals 3, 

 separate, equal, more or less concave or navicular, foliaceous to petalaceous or 

 hyaline; petals 3, separate, equal, ephemeral; stamen 6, fertile, equal, hypogynous; 

 anther sacs reniform (in our species), dehiscing longitudinally, united by a broadly 

 trapezoid connective; filaments (in our species) abundantly pilose; ovary 3-celled; 

 ovules 3 to 6, uniseriate, orthotropous; style filiform; stigma capitate; capsule dry, 

 loculicidally 3-valved; seeds naked, roughly oblongoid to subtrigonal or sub- 

 spherical, more or less rugose and radiately ridged, the micropyle persistently 

 pitted, the funicular scar linear to punctiform. 



About 60 species in temperate and tropical America. 



1. Leaf blade broader than the sheath (at least the upper ones); endemic to 

 south-central Texas 1. T. edwardsiana. 



1. Leaf blade narrower than the sheath or about as broad (2) 



2(1). Sepals glabrous or only the tips eglandular-barbate; distribution in eastern 

 two thirds of Texas and Oklahoma 2. T. ohioensis. 



2. Sepals glabrous or rarely with a few glandular hairs at the base; endemic to 



Trans-Pecos Texas 3. T. Wrightii. 



1. Tradescantia edwardsiana Tharp. 



Roots long and slender, relatively fleshy, very inconspicuously and irregularly 

 pilose; stems erect or ascending, relatively stout, straight, not flexuose, densely 

 and minutely puberulent to glabrate; nodes 3 to 6; internodes to 1 1 cm. long; 

 leaves relatively firm, somewhat subsucculent and crisp, light-green, not glaucous 

 nor subglaucous, the anastomosing secondary veins not evident in desiccation, 

 elliptic-lanceolate, acuminate, gradually constricted into the sheath, 7-30 cm. 

 long, 15-45 mm. broad, minutely puberulent to essentially glabrate, the sheath 

 to 3 cm. long and 2 cm. broad; cymes umbellate, few- to several-flowered, terminal, 

 usually also lateral at the upper nodes, the lateral inflorescences with a definite 

 peduncle; bracts foliaceous, 4-18 cm. long, to 35 mm. broad, widely spreading; 

 pedicels 1.5-3 cm. long, reflexed and somewhat accrescent in fruit, green, minutely 

 and densely puberulent; sepals elliptic, acuminate. 6-9 mm. long, green, not 

 inflated, glandular-puberulcnt; petals broadly ovate, 1-1.2 cm. long, white to 

 pale-mauve, rarely bright-pink; filaments abundantly pilose, the connective 



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