472 TRANS. OF THE ACAD. OF SCIENCE. 
superante; capitulis magnis densissime multi-(30-80)floris; 
floribus majoribus virescentibus demum stramineis ; sepalis 
-ico, with the exclusion of the south-eastern States; but the 
different forms occupy different geographical regions. Var. a 
is found throughout British North America from Canada and 
the Hudson wes regions to the Rocky Mountains and the 
North-west coast, and extends southward to Pennsylvania, 
Porter, Hb. n. 70, Ohio, 6g Michigan, Bigelow, Hb. n. 
and Wisconsin, ap Ste : ave seen no spouse 
Colorado, Parry, Hb. n. (a Seoied form), Ne ew Me exon 
quite characteristic of all the forms of this species. Anot 
peculiarity of var. 8 and 7 is the direction of the leaves, 
especially the upper ones, which are get ages a very 
the shea Var 38 mo icine . ¥ exhibit sometimes 
leaves which has been spoken of in another place. The 
seeds are ().22-0.27 line long, the length being nearly equal 
= cen ed to 24 diameters; commonly 8 ribs are visible on 
on The northern form, var. a, is the genuine J. nodosus of 
Linnzus, who described it trom specimens sent by Kalm 
(most probably from Canada), as Prof. Gray ascertained in 
the Linnzan herbarium itself; at informs me that “ Linneus’ 
