WOOTON AND STANDLEY FLORA OF NEW MEXICO. 125 



1. Lemna trisulca L. Sp. PL 970. 1753. 



Type locality: "Habitat in Europe sub aquis pigris puris." 



Range : Throughout North America, Asia, and Europe. 



New Mexico: Mountains west of San Antonio; Mimbres. Floating in water. 



2. Lemna minor L. Sp. PI. 970. 1753. 



Type locality: "Habitat in Europae aquis quietis." 

 Range: Nearly cosmopolitan. 



New Mexico: Santo Domingo; Sycamore Creek; mountains northeast of Santa 

 Rita; Mule Creek; Nutritas Creek. Floating in water. 



3. Lenana minima Phil. Linnaea 33: 239. 1864, name only ; Hegelm. Lemn. 138. 1868. 

 Type locality: Chile. 



Range : Southwestern United States to South America. 



New Mexico: West Fork of the Gila {Metcalfe 407). Floating in water. 



Order 12. XYRIDALES. 



KEY TO TKE FAMILIES. 



Calyx and corolla free, of very different members; 



stamens free 16. COMMELINACEAE (p. 125). 



Calyx and corolla partly united, of similar mem- 



bers;stamenspartlyadnatetotheperianth. 17. PONTEDERIACEAE (p. 126). 



16. COMMELINACEAE. Spiderwort Family. 



Herbs with simple or branched stems and fibrous or fleshy roots; leaves sheathing 

 at the base, the uppermost often dissimilar and forming a spathe about the flowers; 

 flowers blue or purple; sepals 3, persistent; petals 3; stamens 6, hypogynous; capsule 

 2 or.3-celled. 



KEY TO THE GENERA. 



Perfect stamens 3 or 2; bracts spathelike; petals dissimi- 

 lar; filaments naked 1. Commelina (p. 125). 



Perfect stamens 6 or 5; bracts like the foliage leaves; 



petals similar; filaments hairy 2. Tradescantia (p. 126). 



1. COMMELINA L. Dayflower. 



Perennial herbs with tuberous roots in clusters, sheathing petioles, and linear, more 

 or less succulent leaves; flowers blue, open for only a few hours in the morning. 



key to the species. 



Floral bracts abruptly long-acuminate, 3 to 6 cm. long, glabrous or 

 puberulent; stems frequently simple, never much branched; 

 petals all blue 1. C. dianthifolia. 



Floral bracts short, 2 cm. long or less, usually with long divergent 



hairs on the sides; stems much branched ; one petal white 2. C. crispa. 



1. Commelina dianthifolia Delile in Red. Liliac. 7: pi. 390. 1801. 



Commelina linearis Benth. PI. Hartw. 27. 1839. 



Commelina linearis longispatha Torr. U. S. & Mex. Bound. Bot. 224. 1859. 



Type locality: Described from cultivated plants. 



Range: New Mexico and Arizona to Mexico. 



New Mexico: Common in all the higher mountains from the Las Vegas Mountiiins 

 to the Capitan Mountains and westward across the State. Open slopes, in the Tran- 

 sition Zone. 



The type of C. linearis longispatha came from the Copper Mines. 



