Geum Canadense flavum (Porter) Britton, a valid species. 



By Eugene P. Bicknell. 



This plant is dearly an excellent species and should stand as 

 Getim flavum (Porter). It is common in the vicinity of New York 

 and shows itself to be perfectly distinct from its near relative, Geum 

 Canadense Jacq., with which it is often found associated. Its points 

 of difference from the latter are by no means confined to the size 

 and color of the petals, but involve the pubescence, the form and 

 texture of the leaves the branching of the inflorescence and other 

 less obvious features. As these characters have never been 

 pointed out, it may be useful to draw attention to them. 



Geum flavum is much more coarsely pubescent below than Can- 

 adense, in which the basal petioles and lower part of the stem are 

 often glabrate or only sparsely pubescent ; in flavum the lower 

 stem is hirsute-pubescent, often equally so with Geum Virgimanum 

 L.,the leafstalks spreading-villose. 



The leaves of flavum are mostly larger, thinner and duller 

 green than in Canadense, often becoming very large and lax. The 

 largest in specimens before me are 8' long by f wide on petioles 

 3' in length, dimensions which greatly exceed anything seen in 

 Canadense. The long-petioled basal leaves at flowering time are 

 exceedingly multiform, varying from cordate-orbicular through 

 trifoliate to pinnate with two or three pairs of leaflets, show- 

 ing a much readier tendency to a pinnate form than those of 

 Canadense and to the development of small subleaflets on the peti- 

 ole. The lower cauline leaves reveal the same tendency to 

 greater subdivision than those of Canadense, which are rarely other 



