NAIAD ACEjE. 
393 
3. ZANNICHELLIA, Linn. 
Flowers usually monoicous, a male and female in the same spathe- 
like leaf-sheath. Male achlamydeous, consisting of a single stamen, 
with a filiform filament and 2-4-celled sagittate anther ; pollen sub- 
globose. Female flower with a minute campanulate perianth ; 2-6 
finally pedicellate carpels; ovule solitary, pendulous; style long or 
short, with an oblique peltate stigma. Fruit of 2-6 minute achenes. — 
A single cosmopolitan species with 3 or 4 varieties or subspecies, 
1. Z. palustris, Linn.; var. Z. brachystemon, Gay. Stems 
wide-creeping, filiform Leaves 1-2 inches long, bright green, all sub- 
merged, in. broad. Filament short ; anther 2-celled. Achene 
oblong, in. long, with a distinctly crenate keel, a short pedicel, a 
style half as long as itself, and a large white papillose stigma. Z. 
repens, Bonny . Z. dentata, Lloyd. 
Rodriguez, in streams and estuaries, Balfour ! Cosmopolitan. 
4. HALOPHILA, Thouars. 
Flowers monoicous, solitary in the axils of the leaves, enclosed in a 
2-leaved membranous spathe. Perianth membranous, tubular. Male 
flowers with 3 stamens ; filaments short, monadelphous ; anther 2- 
celled ; pollen confervoid. Female flower with a single ovary, with 3 
parietal placentas, bearing numerous ascending anatropous ovules ; 
style long ; stigmas 3-4, subulate, jointed at the base. Fruit indeliis- 
cent. Seed with copious albumen. — Submarine herbs with creeping 
stems and opposite petioled stipulate membranous leaves. The only 
species. 
Leaves oblong, long-petioled .... 1. H. ovata. 
Leaves ligulate, short-petioled 2. H. stipulacea. 
1 . H. ovata, Gaud, in Frey c. Voy. 430, tab. 4i0,fig. 1 . Stems very 
slender, wide-creeping ; nodes distant, bearing a pair of erect leaves. 
Stipules membranous, obtuse, much shorter than the petioles, which are 
sometimes above an inch long ; blade f-1 in. long, oblong or obovate- 
oblong, obtuse, the ascending veins connected by a distinctly intramar- 
ginal line. Spathes membranous, ovate, acute, in. long, solitary, 
sessile or on short pedicels from the leaf-bearing nodes. Kook. fil. 
FI. Tasm. ii. 45. 
Shores of Mauritius, Rodriguez, and Seychelles. Spread through the tropics 
of the Old World. 
2. H. stipulacea, Aschers. in. Linnaea , xxxv. 172. Stems wide- 
creeping, stouter than in H. ovata. Stipules in., white, membra- 
