ANALYTICAL KEY. ]x1x 
Perianth simple or none. 
Floating or submerged plants . 86 
a5 Terrestial herbs, or, if aquatic, erect ‘from the bottom of the 
water, and projecting from it. : ; : } ; oe 
Trees or shrubs . : ; : : ; : . 7 . 141 
1. Floating Aquatic Plants. 
Small leaf-like fronds, attached two or three together, and 
864 floating without any ‘stem - . LEMNA (p. 421). 
Leaves and flowers growing out of a distinct stem . A Pi i 
87 f Leaves deeply divided = ears lobes . ; =; gS 
\ Leaves entire ; 5 : : 1. 89 
Leaves pinnately divided. Perianth 4-lobed. MyYRIOPHYL- 
LUM (p. 173). 
Leaves repeatedly aeeee Perianth none or many-lobed. 
CERATOPHYLLUM  (p. oe 
88 
Leaves opposite or whorled ‘ : ‘ 
Leaves in a radical submerged tuft . : 188 
Leaves radical in floating tufts . . HYDROCHARIS (p. 434), 
Leaves alternate . ase 
f Tube of the flower long and thread- like, resembling ; a pedicel. 
HLODEA (p. 433). 
eon sessile, or nearly so, in the axils of the leaves, or in 
stalked heads or spikes, without any stalk-like tube . aoe 
{Bes 4-lobed ovary. ‘Two styles. : . CALLITRICHE (p. 397). 
90 
914 Four ovaries, with distinct styles or stigmas NAIADEZ (p. 423). 
One simple ovary and style ; . HIPPURIS (p. 174). 
Flowers axillary. Perianth none, or of 4 small scales. 
NAIADEZ (p. 423), 
Flowers in globular heads, the upper head male, the lower female. 
Perianth none, or of 1 to 6 small scales SPARGANIUM (p. 419). 
Flowers glumaceous. Stamens 2or3 SCIRPUS fluitans (p. 484). 
Perianth of 6 parts. Stamens 6. . JUNCUS articulatus (p. 471). 
Perianth of 5 parts. Stamens about 5 POLYGONUM amphibium (p.386), 
2. Terrestial Herbs, or, of Aquatic, erect. 
Flowers hermaphrodite, containing one or more ovaries and 
one or more stamens : . 94 
93 Flowers diclinous, the stamens and ovaries either in separate 
perianths, or intermixed or variously arranged on the same 
spike, or within the same involucre, but separated by single 
scales only, without distinct perianths . - » 125 
94 Stamens more than 6 . ; ; : : S ao 
Stamens 6orfewer . ; : : . 102 
Stamens indefinite, usually numerous : ‘e : : . 36 
95 Stamens about 12 ; F 3s O¢ 
Stamens 7 to 10 . é ; z : .2 96 
Stamens inserted on the receptacle, Ovaries humerous. 
96 RANUNCULACEZ (p. 1). 
Stamens on the calyx. Ovaries few or single ROSACE (p. 127). 
Perianth 3-lobed. Capsule sessile. : . ASARUM (p. 390). 
97- Perianth (involucre) with 5 small lobes or teeth. Capsule 
stalked . : ° < eos ‘ e EHUPHORBIA (p. 391). 
