Tradescantia Commelinaceae 285 



about 1.25-4 mm wide and nearly as long. This is a tropical species that 

 ranges northward to the southern part of this state. 



N. J. to Kans., southw. to Fla. and Tex., and in tropical Amer. 



3. Commelina virginica L. (Commelina hirtella Vahl.) VIRGINIA Day- 

 flower. Map 591. Found only in the southern part of the state in wet 

 woods and sloughs and along streams. This is our largest species and 

 usually forms colonies. No doubt all early reports of this species for the 

 state should be referred to some other species. Commelina erecta of Gray, 

 Man., ed. 5 is a synonym of this species and Coulter's and Young's reports 

 for it from Jefferson County should be referred to Commelina virginica L. 



Pa. to Kans., southw. to Fla. and Tex. 



4. Commelina angustifolia Michx. Narrowleaf Dayflower. Map 592. 

 This species grows in almost pure, fine sand and is found on sand hills 

 along roadsides, on high, sandy banks of lakes and streams, and on the 

 open dunes about Lake Michigan. Three specimens were measured in the 

 field and the blades of the posterior petals averaged from 17-18 mm wide 

 and 14-17 mm long and the anterior or white petals averaged about 1 mm 

 wide. 



N. C. to Ind., southw. to Fla. and Tex. ; also in Cuba. 



5. Commelina erecta L. (Including the reports of Commelina crispa 

 Wooton from Indiana.) I found a specimen along the roadside 2 miles 

 west of Yankeetown, Warrick County, which I am referring to this 

 species. Pennell (Bull. Torrey Bot. Club 43: 107. 1916) reported two 

 specimens from the dunes about Lake Michigan as Commelina crispa 

 Wooton and I am including them in this species. The name of this species 

 should not be confused with the same name applied to other species by 

 early authors. 



N. Y. to Kans., southw. to Fla. and Tex. 



911. TRADESCANTIA [Rupp.] L. Spiderwort 



[Anderson and Woodson. The species of Tradescantia indigenous to the 

 United States. Contr. Arnold Arboretum 9: 1-132. 1935.] 



Plants glaucous, essentially glabrous throughout, robust, mostly of a dry, sandy 

 habitat; flowering from the first of June through the summer; sepals glabrous 



or with a few hairs at the apex, 8-15 mm long; pedicels 1-1.5 cm long 



1. T. canaliculata. 



Plants not glaucous, more or less pubescent throughout; woodland species of a moist 

 or dry habitat; sepals pubescent, rarely glabrous. 

 Plants dwarf, generally less than 1 dm high, rarely 1.5 dm high, covered all over 

 with long, weak hairs; sepals tinted with pink, about 1 cm long. (See excluded 



species no. 127, p. 1033.) T. brevicaulis. 



Plants usually more than 1 dm high, not covered all over with long, weak hairs; 



sepals very green. 



Stems fiexuous, at least above the lowest inflorescence; leaves lanceolate, the 



median ones usually 2-5 cm wide; flowering from the first of June until frost; 



cymes both terminal and axillary; sepals mostly 6-8 mm long; pedicels 1-1.5 



cm long 2. T. subaspera. 



Stems not flexuous; leaves linear or linear-lanceolate, the median ones less than 

 2 cm wide; sepals 8-15 mm long. 



