PORTULACCA— POTENTILLA. 
147 
pygma'ea, (Ap. Tp.) leaves long-linear, 
wedge-form, obtuse, coriaceous, with the 
branches glabrous ; outer petals obovate- 
(iblong, much larger than the calyx. 6-18 i. 
S. 
grandiJlo'ra,{y-'w. Ap. ^).) leaves wedge- 
(ibovate, obtuse, under surface and branches 
rufous-pubescent ; outer petals obovate, 
much larger than the calyx. 18-24 i. S. 
PORTULACCA. 12—1. (Portulaccece.) [From 
porta, to carry, lac, milk.] 
oleya'cea, (purslane, y. J. 0.) leaves 
wedge-form ; flowers sessile. 
pih'.y,, (@.) leaves subulate, alternate ; 
axils pilose ; flowers sessile, terminal. S. 
POTAMOGE'TON. 4—4. (Junci.) [From 
potamos, a river, and geiton, adjacent, so 
called because it grows about rivers ] 
natans, (pond- weed, g. J. 2^.) leaves 
iong-petioled, floating, lance-oval; at first 
some are sub cordate. On water. 
JLui'taiis, (g. Ju. 11.) lower leaves long, 
linear, upper ones lanceolate, nerved, cori- 
aceous ; all petioled. In water. 
heferophyl'liim, (variegated pond-weed, 
g. Ju. 11.) upper leaves floating, coriaceous, 
elliptical, petiolate, lower ones membranous, 
linear-lanceolate, sessile. 
diversifo'lium, (g. Ju. l^.) upper leaves 
floating, elliptical, petiolate, 5-nerved, lower 
ones filiform ; spike axillary, almost sessile, 
few-flowered. Water. 
per folia' turn, (g. Ju. 11.) leaves a.mplexi- 
caui, cordate, ovate; spike few-flowered, 
on a short peduncle Water. 
lu'cens, (g. Au. 11.) leaves ovate-lanceo- 
late, petiolate, pellucid, and finely veined ; 
epike long, cylindrical. 
crift"piM'm, (r-g. J. 2^.) leaves lanceolate, 
tapering, sessile, undulate, serrate ; spike 
o-iO flowered. Lakes. 
pectina'tum, (g. J. 11) leaves setaceous, 
distichus, alternate, sheathing ; spikes ter- 
minal, interrupted. 
gramin"enm, (grass pond-weed, g. Ju. 
2^.) leaves linear, grass-like, alternate, ses- 
sile ; stipules broad ; stem terete, sub-di- 
chotomous. In July, some of these plants 
begin to raise their spikes of unopened 
flower-buds to the surface of the water ; as 
soon as the stigmas are fertilized by the 
pollen, the spikes are again withdrawn, to 
ripen the fruit under water; others succeed 
them, and the process continues. 
compres"sum., (g. Ju. 1[.) leaves linear, 
obtuse, sessile; stem compressed; spike 
4-6 flowered. 
rosterifo'lium, (g-y. Au. 2.^.) leaves alter- 
nate, linear, closely sessile ; stem flexuous, 
compressed, sub-alate ; branches axillary; 
stipules lance linear, acute ; spikes many 
(20-40) flowered. 2 3 f. 
POTENTIL"LA. 11—12. (Rosacem.) [From 
potentia, power, so named on account of its 
supposed power to heal diseases.] 
A, Leaves digitate. 
canaden"sis, (common five-finger, y. M. 
H.) procumbent, sub-raniose, whitish-silky; 
stipules ovate, gashed ; leaves wedge-ovate, 
gash-toothed ; stem ascending and creep- 
ing, hirsute ; peduncles solitary, elongated ; 
divisions of the calyx lance linear; petals 
orbicular, sub-entire, of the length of the 
calyx. 2-18 i. 
ar gen" tea, (silver five-finger, w-y. Ju. 2/.) 
stem prostrate and ascending, rarely sub- 
erect, branching, white-downy; stipules 
ovate, acute ; leaves wedge-form, gash- 
toothed, silvery white beneath; petals re 
tuse, scarcely longer than the calyx. 4-10 i. 
sim"plex, (y. Ap. 11.) erect, simple, hir- 
sute; leaves oblong-oval, coarsely toothed; 
peduncles axillaiy. solitary, long, 1-flow- 
ered ; petals nearly round, obcordate, 
longer than the calyx. 
sarmento'sa, (y. M. 11.) stem sarmentose , 
leafets obovate, obtuse, serrate, glabrous 
above, hirsute beneath ; petals roundish, 
I longer than the calyx. 
I rec"ta, (y. J. 11.) erect; leaves in fives 
and .sevens ; leafets lanceolate, coarsely 
j toothed ; petals obcordate, larger than the 
I calyx ; corolla large, pale. ' 
B. Leaves pinnate, 
anseri'na, (tansey cinquefoil. y. J. 2/ * 
creeping ; leaves interruptedly pinnate 
numerous, gash-serrate, silky, wbite-down> 
beneath ; peduncles solitary, 1-flowered. 
frutico'sa, (shrubby cinquefoil, y. J. 11.) 
stem fruticose, oblong, lanceolate, entire, 
approximate ; stipules lanceolate, membra- 
nous, acute ; flowers in corymbs, large ; 
petals longer than the calyx. A shrub 2 
feet high, much branched, hairy. Margin 
of swamps. 
pennsylva'nica, (y. Ju. 2^^.) erect, very 
soft, somewhat whitish-villo.se ; leafets ob- 
long, obtuse, sub-pinnatifid, woolly ; panicle 
straight, many-flowered ; segments of the 
calyx semi-oval. 
supi'na, (y. J. ^.) stem decumbent, di- 
chotomous ; leafets oblong, incisely serrate ; 
peduncles axiUary, solitary, 1-flowered. 
argu'ta, (w. J. 1L-) stem erect, pubes- 
cent, viscous above ; leaves unequally pin- 
nate ; leafets somewhat round-ovate, ob- 
lique at the base, doubly gash-toothed ; sti- 
pules sub-entire ; calyx acute, somewhat 
shorter than the corolla. 1-3 f. 
hnmifn'sa, (y. M.) leaves digitate, qui- 
nate ; leafets wedge-oblong, obtuse, ga.sh- 
toothed, white-tomentose beneath ; pedun 
cles short, filiform, procumbent. 4-5 i. S.- 
russellia' na, ( ^ .) the most beautiful spe- 
cies produces rich, dark, scarlet flowers. 
A low shrubby plant. Ex. 
formo'sa, deep red or purple flowers, 
blossoming from May to Augu.st. Ex. 
C. Leaves ternaie. 
tridenta'ta, (mountain cinquefoil, w. Ju. 
11) smoothish ; ' stem ascending, dichoto- 
mous; leaves ternate-palmate ; leafets 
wedge-oblong, coriaceous, 3-ioothed at the 
summit, pubescent beneath ; stipules lance« 
olate, acuminate ; corymb loose, few-flow- 
ered ; petals oblong-ovate, longer than the 
calyx ; stem 3 6 inches high. Mountains. 
Frozen regions to Car. 
nnnoe' gi' ca, (Norway cinquefoil, y. J. 
hirsute ; stem erect, dichotomous abov(» ; 
leaves teraale, palmate ; leafets lauce 
