235] FLORA OF BOULDER, COLORADO 87 



Order lo. ARALES. 

 Family 14. ARACEAE Neck. Arum family. 



82. ACORTTS L. Calamus. 



231. A. Calamus L. Sweet flag. 



Swales along railroad in the city of Boulder, 5300-5400 ft. 

 (Daniels). 



Nova Scotia to Minnesota; Florida to Texas and 

 Colorado: Europe: Asia. 



Family 15. LEMNACEAE Dumort. Duckweed family. 



83. LEMNA L. Duckweed. 



232. L. g^bba L. Gibbous duckweed. 



Ponds near Boulder, 5100-6000 ft. (Rydberg). 

 Nebraska to California; Texas to Mexico: Old World 

 and Australia. 



233. L. minor L. Lesser duckweed. 



Springy swales in the city of Boulder, 5400 ft. (Daniels 

 748). 



Cosmopolitan. 



Order 11. XYRIDALES. 

 Family 16. COMMELINACEAE Reichenb. Dayf lower family. 



84. TRADES CANTIA L. Spiderwort. 



234. T. TJniversltatis Cockerell [T. occidentalis Rydb., not 

 Britton]. University spiderwort. 



Common on the plains, mesas, and foothills, and follow- 

 ing the deeper canons several miles into the mountain re- 

 gion, 5100-7000 ft. (Daniels, 44). The vicinity about Bould- 

 er is the type locality. Both T. scopu/orum Rose and T. oc- 

 cidentalis Britton, according to Rydberg's Flora, occur about 

 Boulder, but the former is a New Mexico plant, while the 

 latter is from Wisconsin. 



Colorado. 



