The Flora of the Cayuga Lake Basin 211 



h. Pubescence spreading, hirsute. 13a. R. repens, 



var. villosus 

 g. Flowers double; leaf divisions subcordate, crenately lobed. 



13b. R. repens, 



var. pleniflorus 

 d. Styles in fruit less than 1 mm. long, recurved. 



e. Leaves with terminal division stalked; base of stem swollen, corm-like; 



sepals reflexed. 14. R. bulbosus 



c. Leaves with all divisions sessile, palmate ; base of stem not swollen ; 

 sepals not reflexed. 15. R. acris 



1. R. longirostris Godr. (R. circinatus of Amer. authors and of Cayuga Fl.) 



White Water-Buttercup. 



In the waters of marshes and bays, in more or less calcareous regions ; infrequent. 

 July-Aug. 



In the marshes at both ends of Cayuga Lake, and in bays along the shores ; also 

 in the Cortland marl ponds (D.\), in Dryden Lake, and in a small pond at South 

 Butler. 



Vt. to B. C, southw. to Tenn., Iowa, and in the Rocky Mts. to Ariz. ; apparently 

 rare or absent on the Atlantic Coastal Plain. 



When the ponds at Cortland dry out, and when the water in Dryden Lake is low, 

 the plant grows emersed on the mud. This species is distinct from R. circinatus 

 Sibth. of Europe. 



2. R. aquatilis L., var. capillaceus DC. (var. trichophyllus of Cayuga Fl.) White 



Water- B uttercup. 



In the waters of pools, marshes, and bays, but more commonly in streams than the 

 preceding species ; infrequent. June 20-July. 



Pools in Beaver Brook (D.) ; Red Mill Pond; upper Cascadilla Creek (D.). 

 Dudley cites also the following localities : " Pools and bayous of Fall Creek and the 

 marshes near. In the pockets of Cayuga L. cut off by the Cayuga So. R. R. Cayuga 

 marshes, abundant " ; however, the plant has not been seen recently in these localities. 



N. S. to B. C, southw. to N. C. and Calif., and on the Atlantic Coastal Plain. 

 Occurs in both calcareous and noncalcareous waters. 



3. R. delphinifolius Torr. (R. multifidus of Cayuga Fl. ?R. flabcllaris Raf.) 



Yellow Water-Buttercup. 



Shallow water of ponds, marshes, and ditches, often among cattails, in mucky 

 soils and Water containing organic matter; scarce. May 15-June 15. 



Near Summit Marsh (D.\), and along the railroad, North Spencer; Jennings 

 Pond; Ithaca flats, along Cayuga St. near Renwick (D. !) ; near the glass works 

 (D.) ; West Inlet Marsh (£>.); Ringwood Swamp; Lockwood Flats, 1827 (Herb. 

 J. J. Thomas, D.) ; Cayuga Marshes; along state road, Montezuma Marshes; marsh 

 e. of Montezuma. 



Cent. Me. to Ont. and Mich., southw. to N. C. and Ark., including the Coastal 

 Plain. 



When growing emersed where pools have dried out, the plant is very different in 

 appearance, with less finely divided leaves (forma terrestris (Gray) Blake, see 

 Rhodora 15: 164, 1913). 



4. R. Cymbalaria Pursh. Sea-side Buttercup. 

 Brackish marshes ; local. June-Sept. 



W. shore of lake opposite Cayuga village; Salt Pond w. of Howland Island; flats 

 e. of Montezuma (Dr. Gray, 1831, also £>.!). 



