COMMELINACEAE 241 



16. Tradescantia comata Small. Stems erect or ascending, 3-5 dm. tall, rarely 

 sparingly branched, very villous : leaf-blades lanceolate or narrowly lanceolate, 1-3 dm. 

 long, acute or short-acuminate, ciliate, villous on both surfaces or glabrate above, somewhat 

 narrowed near the base ; sheaths villous like the stem, 1-3 cm. long : bracts 1-2, like the 

 leaves but smaller : pedicels usually densely villous : sepals oblong or elliptic-oblong, 7-9 

 mm. long, villous, acute or acutish : corolla blue, 1.5-2 cm. broad: capsules oblong, 4-5 

 mm. long, glabrous : seeds oblong, 3 mm. long, tuberculate-ridged. 



In the upper districts and mountains of Georgia. Summer. 



5. TRELEASEA Hose. 



Perennial caulescent herbs, with tuberous-thickened roots. Leaves alternate : blades 

 relatively broad and short. Cymes umbel-like, sessile in an involucre of bracts resembling 

 the leaves. Sepals 3, concave. Petals 3, the claws cohering and forming a slender tube. 

 Stamens 6, all perfect, nearly equal : filaments pubescent, partially adnate to the petals. 

 Capsule stalked. Seeds 2 in each cavity. 



1. Treleasea brevifolia (Torr. ) Rose. Stems often branched at the base, the branches 

 prostrate or decumbent, 2-4 dm. long, leafy to the ends : leaves approximate ; blades thick, 

 oblong to ovate, 3-7.5 cm. long, acute, glabrous except the scabrous-ciliate margins, glau- 

 cous ; sheaths 1 cm. long or shorter, ciliate : bracts 2, similar to the leaves but smaller : 

 cymes many-flowered : pedicels villous : sepals oblong, somewhat villous : corolla white, or 

 pink : petals about 1 cm. long, obovate beyond the claw : filaments pubescent, surpassing 

 the petals : ovary villous at the top. 



In rich soil, southern Texas and northern Mexico. Spring and summer. 



6. COMMELINA L. 



Annual or usually perennial herbs, with mostly spreading stems. Leaves alternate : 

 blades thickish, entire, sheathing at the base. Involucre often peduncled, spathe-like, 

 folded. Flowers irregular, few together in cymes. Sepals 3, unequal, the larger often, 

 partly united. Petals 3, commonly blue, 2 much larger than the third, showy. Stamens 

 3 or rarely 2 : filaments filiform, glabrous, one usually incurved and with a larger anther 

 than the rest. Sterile stamens 2-3, smaller than the fertile. Capsules 2-3-celled, hidden in 

 the spathes. Seeds if 2, one above the other. DAY-FLOWER. DEW-FLOWER. 



Spathes not united at the base. 



Spathes acuminate : capsules 3-celled, 5-seeded. 1. C. nudiflora. 



Spathes acute : capsules 2-celled, 4-seeded. 2. C. communis. 



Spathes with the bases united. 



All three cavities of the ovary with 2 ovules. 



Spathes 1 cm. long or shorter. 3. C. Nashii.' 



Spathes 2-3 cm. long. 



Sheaths at least the lower ones glabrous or nearly so : pubescence if present 



not hirsute. 



Internodes or a portion below the sheaths pubescent or scabrous : root- 

 stocks and roots abbreviated, the latter slender fusiform. 4. C. Swingleana. 

 Internodes at least the lower ones smooth and glabrous : rootstocks and 



roots elongated, the latter cord-like. 

 Spathes pubescent, mainly at the base : sheaths neither pale nor 



loose and inflated. 5. C. angustifoUa. 



Spathes pubescent throughout : sheaths pale, loose and inflated. 6. C. crispa. 



Sheaths usually more or less densely hirsute throughout. 



Spathes pubescent with short hairs and with long hairs near the base or 



along the back. 

 Spathes 2-3 cm. long, acuminate, mainly longer than broad. 



Capsules 2-valved, the dorsal cavity indehiscent. 7. C. Virginica. 



Capsule 3-valved, all the cavities dehiscent. 8. C. erecta. 



Spathes 1-1.5 cm. long, merely acute, mainly as broad as long. 9. C. saxicola. 



Spathes glabrous at least without long hairs near the base. 10. C. elegans. 



Ventral cavities of the ovary with 2 ovules, dorsal cavity with 1 ovule. 11. C. hirtella. 



1. Commelina nudiflora L. Stems usually branched at the base ; branches spread- 

 ing or decumbent and creeping, 3-10 dm. long, more or less diffuse : leaf-blades lanceolate 

 or oblong-lanceolate, 3-10 cm. long, acute, rounded at the base ; sheaths sometimes ciliate 

 or erose : peduncles 1-1.5 cm. long, usually with a line of hairs on the inner side : spathes 

 2-4 cm. long, often thrice as long as broad, acuminate, not united at the base : capsules 3- 

 celled, 7-8 mm. long, apiculate : seeds commonly 5 in each capsule, 3 mm. long, granular. 



In moist and waste ground, New Jersey to Missouri, Florida, Texas, and through tropical America 

 to Paraguay. Spring to fall. 



2. Commelina communis L. Stems erect, or diffusely branched from the base ; 

 branches decumbent and creeping, 3-10 dm. long : leaf-blades lanceolate or oblong-lance- 



16 



