122 OSMUNDA-PARMELLA. 
OSMUND A. 21—1. iPilices.) [From Osmund, who first used it as a medicine.] 
cinnamo'mea, (flowering-fern, y. J. barren frond doubly pinnatifid; seg- 
ments oval, entire ; fertile fronds with opposite racemes, woolly. 3-6 f. 
OSTRYA. 19—12. {AmentacecB.) [From oseon, a bone, on account of its hardness ] 
virgin'Hca, (iron-wood, hop-hornbeam, g. M. T^-) leaves alternate, ovate-ob- 
long, sub-cordate, acuminate, unequally serrate; strobilums oblong-ovate. 
A small tree with very hard and heavy wood. Fertile flowers enlarged 
into a sort of oblong cone, resembling the common hop. Woods. Can. 
to Car. 
OXALIS. 10 — 5. (Gerania.) [From oa^MS, sour, on account of the juice.] 
acetoseV'la, (wood-sorrel, w. r. M, %.) stemless ; scape 1-flowered, longer 
than the leaves ; leaves ternate, broad-obcordate, with rounded lobes; styles 
as long as the inner stamens ; root dentate. 
viola'cea, (violet wood-sorrel, p. J. Ij-.) stemless ; scape umbelliferous, 3-9- 
flowered ; flowers nodding; leaves ternate, obcordate, smooth ; styles shorter 
than the outer stamens. Scape 4-6 i. Rocky woods. 
stric'^ta, (upright wood-sorrel, y. J. (v).) hairy; stem erect, sometimes procum- 
bent, branched ; umbels about as long as the leaves ; leaves ternate, obcor- 
date ; petals obovate, entire ; styles as long as the inner stamens. 4-10 i. 
■ Sandy fields. Flowers small, 4-6 in an umbel. 
OXYCOCCUS. 8—1. (EricecB.) [From oxus, sour, and coccus, a berry.] 
macrocar^'pus, (cranberry, r. J. T2.) creeping ; stem ascending ; leaves oblong, 
fiattish, obtuse, becoming white beneath ; pedicels elongated; divisions of 
the corolla lance-linear ; berry large, bright scarlet. Wet grounds. 
palus"iris, (J. T^.) divisions of the corolla ovate; berries purple, smaller than 
the preceding. Alpine bogs, 
OXYTROPIS. 16—10. {Leguminosa.) 
lombes"tii, (p. Ju. %.) stemless, silky-pilose ; leafets numerous, oblong, acute 
at each end; scape about equal to the leaves; spikes oblong, capitate; 
bracts lance-linear, about equal to the calyx. 
P.^ONIA. 12—3. iPapaveracecb.) [From Pcbon, who is said to have first apphed it to medi- 
cinal purposes.] 
ojicina'lis, (peony, r. J. %.) leaves decompound ; leafets lobed, lobes broad- 
lanceolate ; capsules downy. Ex, 
PANAX. 5—2. (AralicB.) [From pan, all, and akos, inedicine, on account of its great virtues.] 
qninquefo'lia, (ginseng, w. M. %.) root fusiform; leaves ternate, or quinate ; 
leafets oval, acuminate, petioled-serrate. 1-2 f. 
irifo'lium, (dwarf ginseng,) root tuberous, roundish ; stem simple, smooth ; 
leaves ternate; leafets sub-sessile, lance-oblong, .serrate; styles often 3; ber- 
ry 3-seeded. Woods, 4-6 i. 
PANCRATIUM. 6—1. ^Narcissi.) [From pan, all, and krateo, to conquer, supposed by the 
ancients to have been a powerful medicine.] 
mexica'num, (w. M. %.) spatha about 2-flowered; leaves lance-oblong; 6 
teeth of the nectary bearing stamens, 6 simple. 18-24 i. S. 
PANICUM. 3-2. (Gramineat.) 
crus-gal"li, (barn-grass, Au. ©.) racemes alternate and in pairs ; compound 
rachis 5-angled ; glumes terminating in hispid bristles ; sheath glabrous 
2-4 f. 
PAP AVER. 12—1. (PapaveracecB.) [From pappa, pap, so called because nurses mixed this 
plant in children's food to make them sleep.] 
somniferum, (opium poppy, J. @.) calyx and capsule glabrous; leaves clasp- 
ing, gashed, glaucous. Ex. 
rhe'as, (red corn-poppy, r. J. ) capsules glabrous, sub-globose ; stems many- 
flowered, pilose ; leaves gash-pinnatifid. Ex. 
nudicau'le, (y. (^.) capsule hispid; scape 1-flowered, naked, hispid; leaves 
sub-pinnate ; leafets lanceolate, lower ones somewhat gashed. 
PARMELLA. 21—5. iAlgm.) [From ^jarme, shield, and ei7o, to enclose.] 
capera'ta, (shield lichen,) frond orbicular, pale yellow, becoming green, ru- 
gose, at length granulated, dark and hispid beneath; \obes plicate, sinuate- 
