TBIGLOCHIS.] ALISMACE^. 369 



flaccid, faintly grooved on the upper surface. Scape slender, taller. Raceme 

 elongating after flowering, pedicels short. Perianth purple-edged. Antlierss 

 purple. Fruit appressed to the scape. Carpels terete at the back, narrowed 

 below, at length falling away from a 3-quetrous axis. DISTUIB. Europe 

 (Arctic), except Turkey, N. Africa, N. Asia, N.W. India, N. America. 

 2. T. marit'imum, L. ; stems tufted thickened at the base, leaves 

 slightly flattened at the tip, fruit oblong of 6 separable carpels. 

 Salt marshes; fl. May-Sept. Larger and stouter than T. pahtstre; scape 

 curved ; raceme longer, not dense-flowered nor much elongating in fruit ; 

 flowers larger ; fruit not appressed to the scape, and carpels grooved at the 

 back. DISTRIB. Coasts of Europe (Arctic), except Turkey, N. Africa, salt 

 districts of N. and Central Asia, N. America. 



5. SCHEUCH'ZERIA, L. 



A small marsh herb. Rootslock creeping. Leaves erect, slender. Scape 

 leafy ; flowers racemose, bracteate. Perianth-segments 6, herbaceous, re- 

 flexed, connate at the base, persistent. Stamens 6, hypogynous, filaments 

 short ; anthers long, narrow, adiiate to the filament, dehiscing outwards. 

 Ovary of 3 carpels connate at the base, stigma sessile ; ovules 2-3 in each 

 carpel, basilar, anatropous. Fruit of 2-3 inflated spreading follicles. Seeds 

 1-2, erect, ovoid, testa coriaceous. DISTRIB. Europe N. of the Alps 

 (Arctic), N. Asia, Rocky Mts. ETYM. Two Scheuchzers, Swiss botanists. 



1. S. palus'tris, L.; leaves ^-terete, sheaths turgid. 



Marshes, rare, Salop, Notts, Chester, York, Perth ; absent from Ireland ; 

 fl. July. Rootstock, long, slender, clothed with old leaf-sheaths. Leaves 

 6-10 in., with dilated brown sheaths and a gland at the tip. Scape stout, 

 curved. Raceme lax, few-flowered; pedicels much lengthened in fruit. 

 I'triantli-segments linear-oblong. Ripe carpels large for the plant. 



6. BU'TOMUS, L. FLOWERING RUSH. 



A tall marsh herb. Rootstock creeping. Leaves slender, erect. Scape 

 naked. Flowers in a bracteate umbel. Perianth-segments 6, oblong, 

 spreading, subequal, all coloured. Stamens 9, hypogynous, 6 in pairs 

 opposite the outer segments, 3 opposite the inner, filaments subulate ; 

 anthers basifixed, oblong, dehiscence inwards. Carpels 6, beaked, connate 

 below ; styles short, stigmas sessile ; ovules covering the walls of the 

 carpel, anatropous, ascending. Follicles 6, beaked, coriaceous, turgid. 

 Seeds many, minute, ascending, testa thin furrowed ; embryo straight. 

 UISTIUB. Europe, Siberia, Dahuria, W. Asia to N.W. India. ETYM. 

 Obscure. 



1. B. umbella'tus, L.; leaves long slender 3-quetrous, scape terete. 

 Ditches and river-sides from Cumberland and Durham southwards ; naturalized 

 in Scotland ; rare in Ireland ; fl. June-July. Rootstock stout. Leave* 3-4 ft., 

 base sheathing, twisted. Flowers many, 1 in. diam., rose-red ; pedicels J in., 

 lengthening in fruit to 2-4 in. Anthers and carpels red. 



ORDER VII. NA'IADEJE. 



Submerged fresh- or salt-water plants. Rootstock usually creeping. Stems 

 elongate (rarely 0), jointed, branched, slender. Leaves often, floating, 



B B 



