140 UNIVERSITY OF MISSOURI STUDIES [2t>2 



405. R. abortivus L. Small-flowered crowfoot. 

 Woods, open grounds, and waste places; all soils, but in 



dry grounds is apt to pass into the next; common. 



Labrador to Manitoba and British Columbia; Florida 

 to Arkansas and Colorado. 



406. R. micranthus Nutt. [R. abortivus micra?ithus (Nutt.) 

 Gray]. Rock crowfoot. 



Dry rocky woods and thickets; common. 

 Massachusetts to Saskatchewan; Georgia to Arkansas 

 and Colorado. 



407. R. recurvatus Poir. 



Along rills in shade; very scarce in Hinkson creek valley, 

 but more frequent in the region north of More's Lake. 

 Nova Scotia to Manitoba; Florida to Missouri. 



408. R. hispidus Michx. Hairy buttercup. 



In thickets and midland woods, but also in low grounds, 

 where it tends to coalesce with the next. 



Ontario to the Northwest Territory; Georgia to 

 Arkansas. 



409. R. septentrionalis Poir. Marsh buttercup. 

 Alluvial flats and swales,, also moist ledges and ravines. 



Most of the plants are more or less hispid, approaching 

 thus the foregoing, but the styles and achenes appear 

 normal. 



New Brunswick to Manitoba; Georgia to Missouri. 



410. R. fascicularis Muhl. Early buttercup. 



Very rare in the Hinkson creek region along the cliffs. 

 New England to Manitoba; Georgia to Texas. 



158. THALIOTRUM L. [ANEMONELLA Spach.: 

 SYNDESMON Hoffmg.]. Meadow rue. 



411. T. anemonioides Michx. \^A. tkalictroides (L.) Spach.: 

 S. thalictroides (L.) Hoffmg.]. Rue anemone. 



Common in open woods and thickets. 

 New England to Ontario and Minnesota; Florida to 

 Kansas. 



