126 



LEMNACE^. Duckweed Family. 



Spirodella polyrhiza, (L.) Schleid. Greater Duckweed. 

 In ditches, ponds and lakes throughout the state. 



Leiniia trisulca, L. Star Duckweed. 



In ponds and pools; so far it has been collected only 

 from the Missouri river eastward. 



Leiniia minor, L. Lesser Duckweed. 



In ponds, lakes and stagnant water throughout the 

 state. 



COMMELINACE^. Spiderwort Family. 



Tradescantia virgiiiiaua, L. Spiderwort. 



Abundant in low moist ground throughout the state. 



PONTEDERI ACE^e. Pickerel weed Family. 



Heteranthera limosa, (Sw.) Willd. Smaller Mud Plan- 

 tain. 



In muddy ponds near Dell Rapids, in the Sioux val- 

 ley and at various points in the Missouri valley. 



Heteranthera dubia, (Jacq.) McM. Water Star-grass. 

 Schollera graminea, Gray. 



In clear water from the Missouri eastward. 



JUNCACE^;. Rush Family. 



Jimcus effusus, L. Bog Rush. 



Common in low ground in the Sioux valley. 



Juiicus bufonius, L. Toad Rush. 

 In the Black Hills; rare. 



Jimcus tennis, Willd. Slender Rush. 



Common in the Sioux and the James river valleys and 

 in the Black Hills. 



.hi nc us Vaseyi, Englm. Vasey's Rush. 



Near Hot Springs, in the Black Hills. 

 Juiicus lougistylis, Torr. Long-styled Rush. 



Near Lead City, in the Black Hills. 



