Ill 
Upper leaves on longish stalks, either floating, or pro- 
jecting out of the water. 
The lower (submerged) leaves stalked, or else reduced, 
[ to mere leaf-stalks. J 
L na'tans. 
Lower leaves almost or quite without stalks. 
Lower leaves narrow, with not more than 1 or 3, 
longitudinal nerves. | 
heterophyllus.” 
Lower leaves with 5 or more parallel nerves; (var.~ 
rufescens Of) | 
lu'cens.” 
All the leaves submerged, with very short stalks or 
none. 
Leaves all in opposite pairs on the stem, rather~ 
numerous and crowded. 
den'sus./ 
Leaves not opposite (except a pair here and there 
where the stem divides). 
Leaves 3- to 5-nerved, finely toothed, usually much~ 
crisped at their margins. 
cris'pus. 
Leaves 7- or more nerved, not or scarcely crisped, 
not toothed (except lucens). 
Leaves narrowed at their base, or stalked, usually 
toothed near their apex. ) 
lu'cens.? 
Leaves more or less clasping the stem with their 
base, not toothed. 
Leaves rarely twice as long as they are wide, 
f strongly clasping, their apex not hooded. 
perfolia'tus. 
Leaves more than twice as long as wide, slightly 
fo} ) 5 J 
clasping, apex more or less concave and | 
hooded. prelon’gus. 
POTENTIL’'LA. 
Flowers white. 
All the leaves with only 3 hairy leaflets; plant common- 
f on banks, ete. 
q Fragarias trum. Barren Strawberry. J 
Lowest leaves with 5 or 7 leaflets; on rocks (Mont- 
gomeryshire ae Radnorshire). } 
rupes'tris. 
Flowers yellow or purple. 
