ALISMACE^l. 1 47 



II. PETALOI'DEOUS DIVISION. 



Flowers with a perianth coloured like a corolla. 



ORDER XCIV. ALISMA'CEJE. (WATER- PLANTAIN F.) 



Marsh herbs, with flowers having 3 distinct 'sepals and ,'J 

 distinct petals, pistils cither apocarpous or separating at maturity 

 into distinct carpels, and hypogynous stamens 6-many. Flowers 

 on scapes or scape-like stems. Leaves sheathing at the hase, 

 either rush-like or, when broad, mostly heart-shaped or arrow- 

 shaped. 



Synopsis of the Genera. 



* Calyx and corolla both greenish. Carpel* more or less united, but spreading 



at maturity. Leaves rusk like andjleshy, or grass-like. 



1. Triglo'chin. Flowers small, in a spike or close raceme, without bracts. 



Carpels united to the top; when ripe, splitting away from a central 

 persistent axis. 



2. Scheuclize'ria. A low bog-herb, with a creeping jointed rootstock, and 



grass-like leaves. Stamens t>. Carpels 3, globular, nearly distinct. 

 (These two genera are included in Naiadaceao i:i Macoun's Catalogue.) 



* * Cal'jx green, j.ersistent. Corolla white. Pistil apocarpous. Leaves ivith 



distinct blades and petioles. 



3. Alis'ma. Flowers perfect. Stamens usual'}- 6. Carpels numerous in a 



ring. Leaves all radical. Scape ivith u-horled panicled branches. 



4. Sagitta'ria. Flowers monoecious, sometimes Dioecious. S'amcns numer- 



ous. Carpels numerous, in more or less globular heads. Lea\ es arrow- 

 shaped, but varying greatly. Flowers mostly i:i whorls of .3 on the 

 scapes, the sterile ones uppermost. 



1. TRIGLO'CHIN, L. ABBOW-GUASS. 



1- T. palus'tre, L- A slender rash-like plant, G-18 indie; 

 high, found growing in bogs northward. Carpels 3, awl-poinuil 

 at the base, splitting away from below upwards. Spike o. 

 raceme slender, 3 or 4 inches long. 



2. T. marit'imum, L., is also found occasionally. The whole 

 plant is stouter than No. 1, and the carpels are usually 6 in 

 number. 



3. SCHEUCHZE'RIA, L. SCHEUCHZEBIA. 



S. palustris, L. Stem zigzag. Flowers in a loose terminal 

 raceme, with sheathing bracts. Bogs. 



