I04 UNIVERSITY OF MISSOURI STUDIES [246 



168. H. (E.) Engelmanni Steud. 

 Swales; infrequent. 



Massachusetts and Virginia to Texas and California. . 



169. H. (E.) ovata (Roth.) R. & S. \_II. (E.J obtusa Schultes]. 

 All low and limose places, often in water: variable. 



New Brunswick to British Columbia; Florida to Texas 

 and Oregon. 



70. OAREX L. Sedge. 



170. O. Leavenworthii Dewey \C. cephalophora angiisti- 

 folia Boott]. 



Wild meadows and sterile open places. 

 Iowa to Mississippi and Texas. 



171. 0. cephalophora Muhl. 

 Sterile hills; common. 



Maine to Minnesota; Florida to Texas. 



172. O. cephaloidea Dewey. 

 Dry hills and banks; frequent. 

 Massachusetts to Wyoming. 



173. 0. Muhlenbergii Xalapensis (Kunth) Britton. 

 Upland thickets and open barrens. 



New York to Missouri, Texas and Mexico. 



174. O. retroflexa Muhl. \C. rosea retwflexa (Muhl.) 

 Torr.]. 



Oak forests; common. 



Massachusetts to Michigan; Florida to Texas. 



175. O. Texensis (Torr.) Bailey \C. rosea TexensisTorr.']. 

 Oak forests and thickets; scarce. 



Illinois to Alabama and Texas. 



176. O. rosea Schkuhr. 



Rich oak forests; common and variable. 

 Newfoundland to Manitoba; North Carolina to Mis- 

 souri and Nebraska. 



177. O. Sart^wellii Dewey. 

 Swales and ditches; frequent. 



Ontario to British Columbia; New York to Arkansas 

 and Utah. 



