38 LEAFLETS. 
nodes about 2 inches long ; leaves 5 to 8 inches long including 
the j-inch petiole, the blades exactly elliptical as to general 
outline, but the narrow base subcordate, the apex acuminate, 
vivid though deep green above, and glabrous except a single 
series of minute hair-points along midvein and veinlets, beneath 
sparsely short-hairy everywhere, but the hairs of the midvein 
stouter and closely appressed, those of the veinlets more spread- 
ing, the margin also beset with longer stiffer but closely ap- 
pressed hairs. 
Aquatic state. Internodes longer and stem stouter, rooting 
at the nodes though floating: leaves cordate-oblong, 4 to 6 
inches long, the largest 3 inches broad, all acute, but with broad 
cordate base and on stout petioles of 3 or 4 inches, in every part 
glabrous. 
This plant is doubtless common on moist or wet wooded bot- 
toms and shady banks of the upper Mississippi between Iowa 
and Minnesota and Wisconsin, where at various places I have 
seen it, though never in flower. My type specimens were taken 
near LaCrosse, 9 July, 1898, from a colony of plants growing 
on a stone embankment, and near the water’s edge. The 
sheets before me are three, one showing the terrestrial state, 
and two the floating-aquatic condition. The three specimens 
are from one and the same main stem; parts of one plant! 
P. VESTITA. Stoutish, ascending, 2 feet high: leaves ovate- 
lanceolate and lanceolate, acute or acuminate, subcordate at base, 
4 to 6 inches long on stout suberect petioles of about 2 inches, 
both faces canescent with a dense short strigose pubescence, 
that of the midvein beneath longer than that of the surface 
but equally slender and closely appressed ` ocres more canescent 
than the leaves and with asimilar hairiness ; internodes sparsely 
strigose: flowers rather small, in spikes 13 to 3 inches long 
borne scarcely above the leaves on somewhat shorter stout glan- 
dular-hispid peduncles; bracts with back and margin loosely 
long-hairy. 
Next of kin to P. pratincola, but of more westerly range, and 
easily distinguished by its smaller stature and dense almost sil- 
very indument. The best specimen seen is one made by my- 
