Ruppia. | : NAIDACEAE, . 129 
1. R. maritima Linn. Sp. Plant. (1753) 127.—Stems slender, filiform, 
variable in length, 6-24 in., leafy throughout. Leaves 2-5 in. long, filiform, 
with broad membranous sheathing bases. Flowers 2-6 together, at first 
completely enclosed in the inflated leaf-sheath ; but the spike gradually 
emerges, and is borne up to the surface of the water by the usually 
conspicuously spirally coiled peduncle. Ripe carpels ;4,-4 in. long, greenish, 
obliquely ovoid, beaked; each one on a slender stipes sometimes more 
than lin. long.—Hook. f. Fl. Nov. Zel. i (1853) 236; Handb. N.Z. Fi. 
(1864) 279; Benth. Fl. Austral. vii (1878) 174; Cheesem. Man. N.Z. 
Fl. (1906) 751. 
NortH AND Souru Istanps: Abundant throughout in brackish-water ponds and 
lagoons, not so common in fresh-water lakes and streams. December—April. 
All the specimens I have seen have spirally coiled peduncles and rather broad 
sheaths ; but in all probability the variety (or species) rostellata will also be found, 
which has straight or flexuous peduncles and narrow leaf-sheaths. 
4. ZANNICHELLIA Linn. |)7Oa<. 
Slender submerged water-plants; stems filiform, branched. Leaves 
usually opposite, filiform, sheathing at the base; sheaths stipular. Flowers 
minute, axillary, monoecious, a single male and female enclosed in the 
membranous leat-sheaths. Male flower: Perianth wanting. Stamen 1; 
filament short at first, elongating as the flower expands ; anther 2-3-celled, 
linear, basifixed; cells dehiscing laterally, connective produced, apiculate. 
Female flower: Perianth short, cupular, hyaline. Carpels 2-6, sessile ; 
styles long or short; stigma large, obliquely peltate, crenate; ovule 
solitary, pendulous, orthotropous. Ripe carpels usually 3 or 4, sessile or 
stalked, curved, oblong or oblong-reniform, slightly compressed, tubercled 
or crenate or smooth on the back, beaked by the projecting style. Seed 
pendulous ; testa membranous; embryo cylindric, the cotyledonary end 
bent into a short coil. 
An almost cosmopolitan genus of 4 or 5 closely allied species, probably all forms 
of one. 
I. Z. palustris Linn. Sp. Plant. (1753) 969.—Stems very slender, much 
branched, leafy throughout, often forming dense masses, 3-14 in. long. 
Leaves opposite or subwhorled, very slender, 4-3in. long, filiform, flat. 
Flowers sessile or very shortly pedicelled. Fruiting carpels 3 or 4, about 
rgin. long, stipitate or almost sessile, curved, smooth or very obscurely 
crenate on the back; styles from 4 to almost as long as the carpels— 
Hook. f. Fl. Nov. Zel. i (1853) 237; Handb. N.Z. Fl. (1864) 280; T. Kirk 
im Trans. N.Z. Inst. xxviii (1896) 498; Cheesem. Man. N.Z. Fl. (1906) 
752. 
Norte Isnanp: Auckland—Abundant in the Waikato River, from Taupiri down- 
wards, also in Lakes Waikare, Whangape, and Waihi, 7’. Kirk! 7. F.C. Hawke’s Bay 
—Tangoia Lagoon, Colenso! Sours Istanp: Otago—Waikouaiti Lagoon, Petrie / 
December—May. 
The Waikato specimens have the carpels sessile or nearly so, and decidedly turgid ; 
in those from Hawke’s Bay and Otago they are distinctly stipitate, and with longer 
styles. Both forms have the back of the carpel smooth or nearly so. 
5—FI. 
