Triglochin.] cliii. naiadace^ (bennett). 215- 



Order CLIII. NAIADACE^. (By Arthur Bennett.) 



Flowers usually green (often coloured in Jponogeton), 1-2-sexual. 

 Perianth 0, or tubular, or of 3-4 inferior valvate segments. Stamens 

 hypogynous; anthers 1-2-celled. Ovary of 1-4 1-ovuled carpels; style 

 long or short ; stigma of many forms. Fruit of 1 -seeded utricules, 

 achenes, or drupelets. Seeds exalbuminous ; embryo curved or straight, 

 large at the radicular end. — Aquatic or marsh herbs, of various habit. 

 Rootstock usually creeping. Stems simple or branched. Leaves erect, 

 submerged, or floating, sheathing at the base ; stipules 0, or contained 

 in the sheath. 



Genera 16, species about 120, found in all climates. 

 *Stigmas discoid or decurrent on the ovary. 

 Perianth present ; flowers bisexual. 



Marsh herbs ; sepals 6, green . . .1. teiglochin. 



Aquatics. 



Sepals 1-3, white or coloured . . .2. aponogetox. 



Sepals 4, herbaceous . 

 Perianth none ; flowers uni- or bi-sexual. 

 Stamens 2; carpels stipitate 

 Stamen 1 ; carpels usually sessile 

 ^Stigmas subulate or capillary. 



Flowers sessile on a flat linear spadix 

 Flowers axillary ..... 

 Flowera enclosed in membianous sheaths 



3. POTAMOGETON. 



4. EUPPIA. 



5. ZANNICHELLIA. 



6. ZOSTERA. 



7. KAIAS. 



8. CYMODOCEA. 



1. TRIGLOCHIN, Linn. ; Benth. et Hook. f. Gen. PI. iii. 1012. 



Perianth-segments, o or 6, herbaceous, deciduous. Stamens U, at the 

 base of the perianth -segments; anthers with 2 rounded lobes. Carpels 

 3-6, 1-celled, 1-ovuled, 3 often imperfect; styles short, sometimes 

 connate ; stigmas sessile or subsessile, plumose. Fruit of 3 or G free 

 or connate achenes or follicles; tips recurved. Seed erect ; embryo 

 straight. — Marsh herbs with rush-like flat or terete leaves. Flowers 

 small, bisexual, spicate or racemose, 2-bracteate. 



Species about 12, chiefly in the temperate regions of both hemispheres. 



Fruit linear 1. T. hulbosion. 



Fruit subrotuiid 2. T. striatum. 



1. T. bulbosum, Linn. Mant. Alt. 22G. Stem simple, tuberous 

 at the base, with interlaced fibres forming a brown mass at the base. 

 Leaves half -cylindrical, finely striate, channelled, generally shorter than 

 the stem. Raceme elongating after flowering, 0-1 2-flowered. Fruits 

 erect, ascending (not adpressed), larger at the base than the apex, of 

 3 carpels. — Bot. Mag. t. 1445 ; Micheli in DC. Mono«r. Phan. iii. 9i) ; 

 Buchen. in Engl. Jahrb. ii. 510 ; Durand & Scbinz, Conspect. Fl. Afr. v. 



