liuppia.] CXLVIII. NAIADEiE. 1711 



(described sometimes as 4 1-celled anthers), the cells opening outwards ; pollen- 

 grains narrow-oblong, slightly curved, with the ends somewhat dilated. Carpels^ 

 4, at first sessile, but soon protruded on long stalks, each with 1 pendulous ovule- 

 and terminating in a short style or almost sessile broad stigma. Fruiting carpels 

 ovoid or pear-shaped, often oblique, obtuse or more or less produced into a 

 slightly curved beak. — Subsaline aquatic plant, with slender much-branched 

 stems and linear-filiform leaves. 



The genus is limited to a single species, common in salt and brackish lagoons and maishes- 

 in most temperate or subtropical regions of the globe, varying much in the more or less slender 

 foliage, in the beak of the fruit, etc., and divided by some botanists into several species. — Benth 



1. R. maritima (maritime), Linn.; Kunth, Enum. iii, 123; Benth. Fl.. 

 Aiistr. vii. 174. Stems and leaves submerged, filiform, the leaves often very 

 long, the barren ones slightly dilated at the base, the floral ones crowded several 

 together, dilated at the base into thin almost scarious sheaths closely imbricate 

 and completely enclosing the young spike, which soon emerges on a short or long 

 and spirally coiled peduncle bringing it to the surface of the water. Flowers 2 to- 

 about 6, sessile, at first close together, at length often distant. Anthers not ^ 

 line long. Carpels at the time of flowering not exceeding the anthers, but 

 immediately afterwards the anthers fall away, and the stalks of the carpels- 

 lengthen out to from ^in. to above lin. Ripe carpels about 1 line long or rather 

 more. — Hook. f. Fl. Tasm. ii. 42 ; F. v. M. Fragm. viii. 217 ; Nees. Gen. FL. 

 Germ.; Reichb. Ic. Fl. Germ. t. 17. 



Hab.: All along the southern coast. 



5. ZOSTERA, Linn. 

 (From the resemblance of the leaf to a ribbon.) 

 Flowers unisexual, the males and females in alternate rows on the membranous 

 rhachis of a spike enclosed in the sheathing base of the floral leaf. Perianth 

 none. ,Male flowers of a single sessile oblong laterally attached 1-celled anther ; 

 pollen confervoid. Female flowers of a single carpel, laterally attached near the 

 apex and produced above the attachment into a filiform 2-branched style.. 

 Ovule 1, pendulous. Fruit an indehiscent pendulous nutlet. Embryo with a 

 deep longitudinal groove, forming 2 valves which fold over the long curved) 

 linear cotyledonous end. — Marine submerged plants with a creeping rhizome 

 emitting short stems, with long narrow grass-like leaves separating from their 

 narrow sheathing bases by a transverse line. Peduncles axillary or terminal,, 

 bearing a single spike completely enclosed in the slightly dilated but continuous 

 sheathing base of the floral leaf or spatha, which otherwise resembles the stem- 

 leaves. Rhachis of the spike broad and thin, with margins folded inwards and 

 bearing the flowers and fruits only on the inner surface. 



The genus consists of very few species, perhaps reducible to two only, common in most seas- 

 at or near the shores. 



1. Z. nana (small). Both ; Kunth. Enum. iii. 117 ; Benth. Fl. Austr. vii. 176.. 

 Rootstock slender. Leaves narrow-linear, rarely above 1 line broad, varying in 

 length from a few inches to 1 or 2ft., usually truncate or notched at the end, 

 with 1 conspicuous central nerve and 1 or 2 lateral ones on each side often scarcely 

 apparent. Peduncles 4 to lin. long, the floral leaf or spatha usually rather 

 narrower than the othe'rs, except the sheath which is \ to fin. long and above 

 a line broad, the margins quite closed over the spike but not connected, the 

 stigmas usually protruding at the time of flowering. Rhachis of the spike thin 

 and membranous, lining the inside of the sheath but free from it, the margins 

 folded inwards and bearing just within the edge on each side 2 or 3 vertical plates 



