LEMNACEAE. 75 



Parlin, Gunnison Co.; Van Boxle's ranch, above Cimarron; near Grand 

 Lake; Spicer, Larimer Co. 



2. Lemna gibba L. In ponds from Nebr. to Cal., Tex. and Mex. ; also in 

 the Old World and Australia. Alt. 3500-12,500 ft. Pike's Peak; near 

 Boulder. 



3. Lemna minor L. In still water and slow streams from Lab. to Alaska, 

 Fla. and Mex.; also in the Old World and Australia. Alt. 4000-9000 ft. 

 Trinidad; along Uncompahgre River, near Ouray; Ironton Park, 9 miles 

 south of Ouray; Hayden, Routt Co. 



Order 15. XYRIDALES. 



Calyx and corolla free, of very different members ; stamens free. 



Fam. 22. COMMELINACEAE. 



Calyx and corolla of quite similar members and partly united ; stamens partly 

 adnate to the perianth. Fam. 23. PONTIDERIACEAE. 



Family 22. COMMELINACEAE. SPIDERWORT FAMILY. 



Perfect stamens 3, rarely 2 ; petals unequal ; bracts spathe-like. 



i. COMMELINA. 

 Perfect stamens 6, rarely 5 ; petals all alike ; bracts leaf-like. 2. TRADESCANTIA. 



i. COMMELINA. DAY-FLOWER, DEW-FLOWER. 



i. Commelina crispa Wooton. In sandy soil from Mo. to Neb., Colo., Tex. 

 and N. M. Alt. 4000-6500 ft. Caiion City. 



2. TRADESCANTIA L. SPIDERWORT. 



Flowers 11.5 cm. in diameter; plant glabrous or calyx and pedicels sparingly 

 glandular; leaves 4-6 mm. wide. i. T. scopiilorum. 



Flowers 2-3 cm. in diameter ; calyx and pedicels usually densely glandular-pube- 

 scent ; leaves 6-8 mm. wide. 2. T. occidentalism 



1. Tradescantia scopulorum Rose. In moist ground from Black Hills of 

 S. D. to Colo., N. M. and Ariz. Alt. 4000-5000 ft. Boulder; Denver; Colo- 

 rado City. 



2. Tradescantia occidentalis Britton. On sand-hills and in rocky ground 

 from Neb. to Mont., Tex. and N. M. Alt. 4000-6000 ft. Denver ; Eads ; New 

 Windsor; Fort Collins; Walsenbufg; near Boulder; Pennock's mountain 

 range ; Spring Canon ; Horsetooth Gulch ; Wray. 



Family 23. PONTEDERIACEAE Dumort. PICKERELL-WEED FAMILY. 

 i. HETERANTHERA Willd. 



i. Heteranthera limosa (Sw.) Willd. In shallow water or mud from Va. 

 to Neb., Fla. and La. and Colo.; also W. Ind., Mex. and Cent. Am. Alt. 

 4000-5500 ft. Between Longmont and Loveland ; eastern Larimer County ; 

 west side of Cache La Poudre ; Limnath Co. 



