ANALYTICAL KEY. 29 



Stamens 6, dissimilar, or only three with perfect anthers. 

 Sepals 3, herbaceous; ephemeral petals 3, unequal. 



COMMELINACE^:, 538 



Perianth tubular, 6-lobed PONTEDERIACE^;, 535 



Stamens 3, similar. Moss-like aquatic. . . . MAYACE^:, 537 

 Perianth wholly glumaceous, of 6 similar divisions. . JUNCACE^E, 539 

 Perianth partly glumaceous or chaff -like ; flowers in very 



dense heads. Rush-like or aquatic. 

 Flowers perfect ; inner perianth of three yellow petals ; 

 perfect stamens and plumose sterile filaments each 

 3 ; pod 1-celled, many-seeded on 3 parietal placentae. XTRIDACE.E, 536 

 Flowers monoecious or direcious, whitish-bearded ; sta- 

 mens 4 or 3; pod 2 - 3-celled, 2 - 3-seeded. . ERIOCAULE^E, 566 

 C. GLUMACEOOS DIVISION. Flowers destitute of proper perianth, except 



sometimes small scales or bristles, but covered by scale-like bracts or glumes. 

 Glume a single scale-like bract with a flower in its axil. . CYPERACE^E, 567 

 Glumes in pairs, of two sorts. GRAMIXE.E, 623 



CLASS III. CEYPTOGAMOUS ACKOGENS. (See p. 17.) 



SUBCLASS I. PTERIDOPHYTES : with woody fibres and vessels. 



Spores of only one kind ; spore-cases 



Borne beneath shield-shaped scales in a terminal spike ; stems 



naked, sheathed at the nodes EQUISETACE^E, 675 



On the back or margin of fronds circinate in vernation. FILICES, 678 



Bivalvular, in special spikes or panicles ; fronds erect in vernation, 



from short erect rootstocks. . . . OPHIOGLOSSACE.E, 693 



Solitary in the axils of leaves, 2 - 3-valved ; low long-stemmed moss- 

 like evergreens; leaves small, in 4-16 ranks. LYCOPODIACE^E, 695 

 Spores of two kinds, large and small ; spore-cases 



Solitary in the axils of small 4-ranked leaves, or in the bases of 



linear radical leaves. .... SELAGINELLACE.<, 697 



Enclosed in peduncled sporocarps ; leaves 4-foliolate. MARSILIACE^E, 700 



Sporocarps sessile beneath the stem ; small, floating, pinnately 



branched, with minute imbricate leaves. . SALVINIACE^:, 701 



SUBCLASS II. BRYOPHYTES : with cellular tissue only. [Cap- 

 sules not operculate, containing spores and usually elaters, in the fol- 

 lowing Orders.] 



Capsule 4-valved, pedicellate ; plants leafy-stemmed, rarely thallose. 



JUNGERMANNIACE.E, 702 

 Capsule 2-valved or valveless ; plants thallose. 



Thallus without epidermis ; capsule with a columella, short-pedi- 



celled or sessile on the thallus. . . AXTHOCEROTACE^E, 726 

 Capsules borne beneath a pedunculate receptacle. MARCHANTIACEJE, 727 

 Capsules immersed in the thallus or sessile upon it, indehiscent. 



RICCIACE.E, 730 



