ANALYTICAL KEY. 25 



B. FLOWERLESS OR CRYPTOGAMOUS. Plants not producing flow- 



ers, propagated by spores. 

 With many-jointed stems and no leaves, except the united scales or 

 teeth that form a sheath or ring at each joint : spore cases in a 

 terminal head or spike ..... HORSETAIL F. 486 

 With ample leaves often compound, all from a rootstock or trunk, 



and bearing the minute spore cases 



Herbage circinate, or rolled up in the bud . . FERN F. 486 

 Herbage erect (not rolled up) as it unfolds, 



ADDER'S TONGUE FERN F. 01 



With scale-shaped, linear, or awl-shaped and wholly simple leaves 

 thickly set on the leafy stems : spore cases in the axil of some 

 of them 



Spores all of one kind ..... CLUB MOSS F. 501 

 Spores of two unlike kinds . . .. SELAGINELLA F. 503 



APPARENT EXCEPTIONS TO THE CLASSIFICATORY SCHEME. 



1. Key to those exogens which from their foliage might perhaps be mis- 

 taken for endogens. 

 Pistils indefinitely numerous: herbs, polypetalous, 



(Myosurus and some species of Ranunculus) CROWFOOT F. 34 

 Pistils 3-12, separate 



Leaves peltate or round heart-shaped : aquatic, polypetalous, 



WATER LILY F. 51 

 Leaves heart-shaped : marsh plants, apetalous, also destitute of 



calyx PEPPER F. 374 



Leaves thick and fleshy: polypetalous or some few monopeta- 



lous : flowers completely symmetrical . . ORPINE F. 170 

 Pistil one, but the ovary deeply 3-20-lobed or horned and style sepa- 

 rate : leaves thick and fleshy : polypetalous, 



FIG MARIGOLD F. 199 

 Pistil one, the ovary 4-lobed, and sessile stigmas separate: leaves 



slender: aquatics WATER MILFOIL F. 175 



Pistil one : ovary not lobed : polypetalous 



Petals usually very numerous : ovary many-celled, many-seeded : 



aquatics WATER LILY F. 51 



Petals with the sepals usually very numerous : style 1 : ovary 

 1-celled, many-ovuled : fleshy, leafless plants, 



CACTUS F. 195 

 Petals and styles, also the stamens 5: ovary 1-celled, 1-ovuled, 



LEADWORT F. 271 

 Petals 5: styles 2 or 3: ovary 1-celled, many-ovuled, free from 



the calyx : leaves opposite . (Dianthus, etc.) PINK F. 73 

 Petals 5: styles 2: ovary 2-celled,2-ovuled: teeth of the calyx on 

 its summit : leaves alternate, 



(Eryngium, etc.) PARSLEY F. 200 

 Petals 5or3: style only one, not lobed 



Calyx free from the 1-celled simple ovary : stamens 

 numerous 



(Acacias with phyllodia) MIMOSA SUBF. 122 

 Calyx adherent to the several-celled ovary : stamens 8 or 10, 



MELASTOMA F. 176 



Pistil only one, both as to ovary and style : monopetalous 

 Stamens 5 : style 3-cleft at the apex: pod 3-celled, 



POLEMONIUM F. 295 

 Stamens 4 : style and stigma one : corolla 4-cleft, dry and scari- 



ous : pod 2-celled : leaves ribbed . . PLANTAIN F. 356 

 Stamens 8 or 10: style and stigma one: corolla becoming dry 



and scarious : leaves narrow . (Heaths) HEATH F. 262 

 Pistil, if it may be so called, an open scale, or none, 



GYMNOSPERMS, 476 



