KEY TO THE NATUEAL ORDERS. 



134. Leaves oblong; flowers white or pink, 1-1 in. diametgr... xxvii. Saxifragaceoe. 

 Leave.s mostly linear, spiney ; flowers small, yellow, often 



in dense heads xxv. Legummoscc. 



135. Flowers i-1 in. long, showy, and "very irregular Iviii. Labiatop.. 



Flowers regular, or very nearly so 136. 



136. Leaves 1-2 lines long, pale, silky, closely overlappin.i?, 



in 2 opposite rows liii. Oonvolvulacea'. 



Leaves 2-4 lines long, narrow, oblong, glabrous or 



nearly so; corolla conspicuous x. Frankeniacece. 



Leaves usually exceeding 4 lines, generally broad 137. 



137. Stamens 2 or 8 ; corolla 4-lobed, conspicuous 138. 



Stamens 4, 5, or 6 ; corolla 5-lobed, or if 4-lobed incon- 

 spicuous 139. 



138. Corolla blue or white, spreading; petals united; stamens 2. Iv. Scrophulariaci'm. 

 Corolla green, white, or red; petals cohering to one 



another; stamens 8 xxi. Butacece. 



139. Stamens and pistil in the same flower, the former short, 



and enclosed in the corolla-tube, or forming a cone over 



the pistil; ovary superior xlix. Apocynacece. 



Stamens and pistil on separate flowers; the former long 

 and pendulous; ovary inferior xxxix. Bubiacece. 



140. Flowers small, obscure, solitary to many, sessile or nearly 



so, axillary or terminal 141. 



Flowers conspicuous, often showy 144. 



141. Leaves reduced to scales; fruit in cones Ixxi. Casuarinece. 



Leaves normal 142. 



142. Leaves flat, linear ; flowers in small, white, sessile clusters 



in the leaf-axils; the perianth and bracts rigid ... Ixii. Amarantacecc. 



Leavesi broad or cylindric, rarely flat and narrow ; perianth 

 succulent 143. 



143. Perianth white or yellow ; stamens 2 ; leaves flat, linear to 



ovate Ixviii. Thymeliacea. 



Perianth green ; stamens usually 5 ; leaves cylindric, or, if 

 flat, angled Ixi. Ohenopodiaceoi. 



144. Stamens 2; flowers under i in., white or yellow, often 



clustered into heads Ixviii. Thymeliaceoe. 



Stamens numerous, or, where absent, the pistil formed of 

 many carpels 145. 



145. Leaves entire; ovary inferior xxxi. Myrtacem. 



Leaves usually toothed or divided; pistil superior 146. 



146. Leaves shining, acutely toothed; anthers valvate : tree ... Ixv. Monimiacece. 

 Leaves dull, with a plain or obtusely-toothed margin, 



often divided; creeper or short simple under-shrub ... i. Banunculacece. 



147. Plant 1-2 in. long, subterranean, the flower alone 



coming to the surface, and about i in. long, oblong, 



crimson and yellow Ixxvi. Burmanniaccm. 



Plant green, growing on soil or in water 148. 



148. Plant minute, scale-like, floating or submerged ; roots 



abortive Ixxxiii. Lemnacece. 



Plant with distinct stem and leaves 149. 



149. Flowers minute, very numerous, in dense velvety spikes, 



several inches to a few feet long 150. 



Flowers otherwise disposed 15l| 



160. Leaves flat, i-1 in. wide ; flowers brown, obscure ; 



water plant. Ixxxii. Typhace.cE. 



Leaves rush-like, angled, very numerous ; flowers whitp 

 herbaceous; land plant Ixxix. liliacecn. 



151. Flower and fruit enclosed in overlapping scarious bracts- 



perianth obscure, often absent 152. 



Perianth of 6 equal scarious parts Ixxxi. Juncacea>. 



Perianth wholly, or at least the inner whorl, herbaceous, 

 usually conspicuous; if obscure or without a perianth, 

 never surrounded by scarious bracts I55 



