I06 UNIVERSITY OF MISSOURI STUDIES [248 



185. O. cristatella Britton \_C. tribuloides cristata Bailey]. 

 Very common in low grounds. 



New Brunswick to Manitoba; Pennsylvania to Missouri 

 and Nebraska. 



186. O. scoparia Schkuhr, 

 Grassy swales; rather infrequent. 



Nova Scotia to Manitoba; Florida to Colorado. 



187. C. straminea Willd. 



Fields and copses; frequent and very variable. 

 New Brunswick to Manitoba; North Carolina to the 

 Indian Territory. 



188. O. mirabilis Dewey \C. straminea mirabilis (Dewey) 

 Tuckerm.]. 



Thickets and open uplands. 



New Brunswick to Manitoba; Georgia to the Indian 

 Territory. 



189. O. tenera Dewey \C. straminea aperta Boott]. 

 Swales; frequent. 



Maine to Ontario; Virginia to Louisiana; Iowa and 

 Missouri. 



190. 0. Jamesii Schwein. 



Oak woods and thickets; common. 



New York and Michigan to Iowa; District of Columbia 

 to the Indian Territory. 



191. 0. crinita Lam. 



Wet swamps; rare and local. 



Nova Scotia to Ontario; Florida to Texas. 



192. O. pubescens Muhl. 



Rich woods and thickets; locally abundant. 



Nova Scotia to North Dakota; New Jersey to Missouri. 



193. 0. umbellata vicina Dewey. 



High pasture on a bluff of Hinkson creek, east. 

 Nova Scotia to the Northwest Territory; New Jersey 

 to Missouri. 



