CLASS IV. 147 
shorter than the calyx and coriaceous: rudiments opposite, sessile, e- 
sembling vaives: nectary lateral—<(ribbon-grass.) 
C. Spikelets many-flowered. 
‘Po’a. Spikelets oblong or linear, compressed, many-flowered; ca- 
lyx shorter than thelorets: corolla herbaceous, awnless, often arach- 
aoid at the base; lower valve scarious at the margin.—(spear-grass. ) 
Exotic. 
Sore”’num. Florets in pairs, one perfect, with a 3-valved corolla, 
and sessile; the other staminate or neutral, and pedicelled.—(broom 
corn. 
are Spikelets aggregated in unilateral heads, many flower- 
ed: calyx shorter than the florets, with one large glume, keeled, point 
ed: corolla with the lower valve keeled, emarginate, mucronate. 
(orchard grass.) 
Ave/na. Calyx 2-valved; 2, 3, or many flowered: corolla valves 
mostly bearded at the base, lower one torn, with a twisted awn on the 
back: glumes membranaceous, and somewhat follicle-like; seed 
coated.—(oats.) 
mm D. Flowers in spikes. 
Triticum. Calyx 2-valved, about 3-flowered ; florets sessile on the 
teeth of the rachis, obtusish and pointed; glumes beardless, or inter- 
ruptedly bearded.—-(wheat.) 
Seca’Le. Calyx 2-valved, 2 or 3-flowered: spikelets sessile on the 
teeth of the rachis, with the terminal floret abortive: glumes subulate, 
opposite, shorter than the florets: corolla with the lower valve long- 
awned.—-(rye.) 
CLASS IV. TETRANDRIA. Four Stamens. 
Order 1. Monogynia. One pistil. 
A. Flowers superior. 
(1-petaled.) 
CepraLan”’tuus. Inflorescence in a head: general calyx none; 
proper calyx superior, minute, angular, 4-cleft: corolla funnel-form ; 
receptacle globular, hairy: seed solitary, oblong.—(button-bush.) 
Housto’nia. Calyx half superior, 4toothed: corolla salver-form, 
4-cleft; capsule 2-celled, many-seeded, opening transversely.—(inno- 
cence.) 
(4-petaled.) 
_Cor’nus. Calyx 4-toothed: drupe with a 2-celled nut Some spe- 
cies have a 4leaved involucrum.—(dogwood, false box.) 
Southern. 
Ly’cwm. Corolla tubular, having the throat closed by the beards of 
the filaments: stamens often 5: berry 2-celled; many seeded.—(mat- 
rimony.) 
