ANALYTICAL KEY. lxix 



Perianth simple or none. 



f Floating or submerged plants 86 



a - ] Terrestial herbs, or, if aquatic, erect from the bottom of the 



1 water, and projecting from it 93 



(/-Frees or shrubs 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 . . .87 

 g7 f Leaves deeply divided into capillary lobes . . . .88 



\ Leaves entire 89 



{Leaves pinnately divided. Perianth 4-lobed. Myeiophyl- 

 lum (p. 173). 

 Leaves repeatedly forked. Perianth none or many-lobed. 

 Ceeatophyllum (p. 397). 

 {Leaves opposite or whorled 90 

 Leaves in a radical submerged tuft 136 

 Leaves radical in floating tufts . . . Hydeochaeis (p. 434). 

 Leaves alternate 92 



f Tube of the flower long and thread-like, resembling a pedicel. 

 90 I Elodea (p. 433). 



1 Flowers sessile, or nearly so, in the axils of the leaves, or in 

 t stalked heads or spikes, without any stalk-like tube . . 91 

 f One 4-lobed ovary. Two styles . . . Calliteiche (p. 397). 

 91 4 Four ovaries, with distinct styles or stigmas Naiades (p. 423). 

 [One simple ovary and style .... Hippueis (p. 174). 

 ''Flowers axillary. Perianth none, or of 4 small scales. 



Naiades (p. 423). 

 Flowers in globular heads, the upper head male, the lower female. 



Perianth none, or of 1 to 6 small scales Spaeganium (p. 419). 

 Flowers glumaceous. Stamens 2 or 3 SCIEPUS 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, if Aquatic, erect. 

 'Flowers hermaphrodite, containing one or more ovaries and 



one or more stamens 94 



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 



Stamens more than 6 . . . 95 



Stamens 6 or fewer . . 102 



J Stamens indefinite, usually numerous 96 



954 Stamens about 12 97 



( Stamens 7 to 10 98 



{Stamens inserted on the receptacle. Ovaries numerous. 

 Ranunculace^e (p. 1). 

 Stamens on the calyx. Ovaries few or single Rosaceje (p. 127). 

 Perianth 3-lobed. Capsule sessile . . . Asaeum (p. 390). 

 Perianth (involucre) with 5 small lobes or teeth. Capsule 

 stalked Euphoebia (p. 391). 



92 ^ 



934 



94J 



