Victorian Plants. 423 



VALLISNERIA. 



1818. Leaves largely or totally submerged, somewhat trans- 



parent. 



Leaves broad -linear, almost blunt, with any denticulation 

 only at and near the summit ; sepals of the staminate 

 flowers minute, ovate-lanceolar, membranous ; calyx-lobes 

 of the pistillate flowers rather firm, lanceolar-ovate ; 

 stigmas sessile, cleft, subtile-papillular ; fruit thinly cylin- 

 drical ; seeds minute, ellipsoid. V. spiralis. 



HAXiOPHXXiA. 



1819. Leaves from narrow- to broad-elliptical, long-stalked. 



Dwarf, submerged, creeping ; leaves basal, transparent, 

 entire, occasionally five times longer than broad ; primary 

 venules three, one carinular, two intra-marginal ; second- 

 ary venules subtile, costular ; anthers cordate-ovate, 

 almost sessile ; fruit ovate-ellipsoid, the surrounding 

 calyx-tube pellucid ; seeds almost globular. 



(H. ovalis.) H. ovata. 



EXiODEA. 



1820. Leaves usually from elliptical- to linear-lanceolar, 



often serrulated. 



Much submerged, elongated, branched ; leaves three or four 

 or seldom more in the numerous whorls or some simply 

 opposite, of tender texture ; flowers solitary ; the stami- 

 nate on a short stalklet, the pistillate sessile ; stamens 

 and stigmas usually three ; fruit slender ; seeds few or 

 several, ellipsoid, but the outer membrane slightly pro- 

 tracted at both extremities. 



(Hydrilla verticillata. ) E. verticillata. 



DE AE. 

 SISYRINCHIUBI. 



1821. Calyx-lobes and petals blue. 



Often somewhat tall ; leaves long, rather rigid, broad-linear, 

 much pointed, mostly distichous -basal ; floral leaves 

 shortened ; flowers rather large, in paniculated clusters, 

 each lasting only one day ; bracts broad, crowded, con- 

 cealing the calyx-tubes ; calyx-lobes and petals almost 

 obovate ; stamens and pistil shorter than the petals ; 

 filaments almost disconnected ; fruit ellipsoid, somewhat 

 angular ; seeds brown. S. cyaneum. 



