NEW WESTERN RANUNCULACEZE. 121 



Distinguished from all the species described in Bornet & 

 Flahault, Eevision des Nost. Het, by the very slender tri- 

 chomes; and from C. limicola Kirchuer, Algenflora Schles- 

 iens, p. 237, and C. minutum, Wood, F. W. Algge of the U. S., 

 by the cylindrical cells with joints not constricted. Its sys- 

 tematic position is next to C. muscicola Kuetz. 



Found among other algse in a scum in a ditch, Maiden, 

 Mass., Oct. 12, 1890. 



NEW WESTEEN KANUNCULACE^. 

 By Edwakd L. Greene. 



Ranuuculus eremogenes. Annual, erect, 1 to 2| feet 

 high, stout and fistulous, sparingly leafy, simple below, 

 loosely corymbose-paniculate above, glabrous, the herbage 

 light-green: leaves of rounded general outline, mostly 5- 

 parted and the segments cleft into about 3 lobes, these 

 toothed: flowers 4 or 5 lines broad; light yellow petals sur- 

 passing the sepals: head of numerous small achenes obtusely 

 ovoid, the oblong-ovoid receptacle much inflated: achenes 

 minute, thick, little compressed, nearly beakless. 



Plant of wet springy places and margins of pools in the 

 West American desert regions, from along the eastern base of 

 the Colorado Eocky Mountains, through the Great Basin, 

 and to southeastern Oregon and northwestern British 

 America; the American counterpart of the Old World R. 

 sceleratus, to which it has been erroneously referred, being 

 the B. sceleratus, var. multifidus of Nuttall. But the more 

 dissected foliage is only one of several good characters ex- 

 hibited by this neglected species. Its comparatively leafless 

 stem and light yellowish green herbage are in very marked 

 contrast with the copious leafiness and the vivid green of R. 

 sceleratus. Its flowers are thrice as large; its heads of 

 achenes much shorter and thicker; while the achenes them- 



