ITAIIDIC'S^. (POND-WEll) FAMILY.) 825 



ledon long-acuminate, coiled — Slender, branching herbs growing 

 under water, with filiform, entire leaves, and sheathing, membranous 

 stipules. 



Z. palii§tri§, L. 71 Carpels 2-C, crowded into a little umbel, 

 short-peduncled, obliquely oblong or semilunar, unarmed or with 

 dorsal or sometimes ventral margin, crenate-dentate — May and June — 

 Water ; common throughout. 



Var. g-eiiuiua, Asch. Peduncle of staminate flower longer. 

 Fruit short-pedicelled, more or less dentate, twice to thrice as long as 

 style ; stigma denticulate. 



Var. pcdiccllata, Asch. Peduncle of staminate flower shorter. 

 Pedicels about as long as carpel; stigma obscurely denticulate. 



5. ZOSTERA, L. Grass-Wrack. Eel-Grass. 

 Flowers perfect, naked, consisting of an anther above an ovary. 

 Cells of anther connected by a semilunar crest, 1-3, dehiscent by 

 longitudinal slits; pollen confervoid. Ovary spurred below, ending 

 in a style, which is divided into two, band-like stigmas. Ovule 

 pendulous. Fruit cylindrical, membranous, indehi scent. Embryo 

 large — Submerged, marine herbs, with a creeping, orange-colored 

 root-stock, rooting at nodes, the older portions soon rotting, the 

 interned es usually curved. Branches erect, some short, sterile, others 

 branched, fertile. Leaves two-ranked, sheathing, ligulate, the lamina 

 linear, entire, rounded and usually notched at tip. Flowering stem 

 flattened, inflorescence spiked, alternately 3 -ranked at the anterior 

 face of the tip of the axis (spadiv), included in the split sheath of the 

 uppermost floral leaf (spatJie). 



1, Z. marina, L. !(. Stout. Sheaths of all but floral leaves 

 closed, destitute of auricles, the lamina rounded or notched at tip, 3-5-9- 

 nerved, the lateral nerves distant from margin — Spathe as iDroad as 

 peduncle; flowers numerous, usually destitute of bracts; fruit longitu- 

 dinally grooved — Summer — Sandy and muddy bottom of sea to a 

 depth of 10 metres. 



2. Z. nana. Roth. If Slender. Sheaths of leaves split, 2-auricled, 

 the lamina narrow-linear, entire at tip, 3-nerved, the lateral nerves at 

 margin. Spathe much broader than peduncle; flowers 3-13, bracted; 

 fruit not grooved — Summer — At bottom of sea, to a depth of 

 3 metres. 



6. CYWEODOCEA, Ko2nig. Cv.modocea. 

 Flowers dioecious, naked. Staminate Jioicers : anthers 3, 4-celled, 

 inserted on a peduncle as long as they, connate, their cells splitting 

 lengthwise, ending in a subulate beak. Pollen confervoid. Pistillate 

 floicers: carpels 3, side by side, each ending in two stigmas; ovule 1, 

 pendulous from tip of carpel, nearly orthotropous; carpel at maturity 

 compressed, semi-ovate or semi-elliptical, bony, iudehisceut. Seed free, 

 testa separable. Embryo with a thick stalk, the radicle lateral, the 

 cotyledon cylindrical, appresscd above in the axis, enclosing in its 

 sheath a well formed plumule — Submarine plants, with creeping root- 

 stocks rooting at nodes, and ringed with the scars of the fallen leaves. 

 Leaves in two rows, and, with the exception of the first leaves of the 

 branches, frondose, their sheaths open, more or less two-auricled, pro- 

 duced into a strap at the base of the lamina. 



107 



