Caltha

1. Stems creeping or floating, rooting at nodes; flowers whitish; sepals ca. 4–8 mm long.

C. natans

1. Stems ± erect, not rooting at the nodes; flowers bright yellow; sepals ca. 11–27 mm long.

C. palustris

All species found in Caltha

Caltha natansFLOATING MARSH MARIGOLD 
Caltha palustrisMARSH-MARIGOLD, COWSLIP 

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. March 28, 2017. http://michiganflora.net/genus.aspx?id=Caltha.