226 CLIII, NAIADACEE (BENNETT). | .Vaias. 
muricate stems. Leaves linear, entire, or toothed, alternate, opposite, 
or whorled. Flowers dicecious or monecious, axillary and small. 
Species about 32, in all temperate and tropical regions. 
Dicecious - - - . - = . 1. N. marina. 
Moneecious. 
Male and female flowers without a spathe : . 2. N. graminea, 
Male and female flowers in a spathe. 
Female spathe with a terminal outgrowth . . 3. WV. affinis. 
Female spathe without a terminal outgrowth. 
Sheaths with short obtuse auricles 
Sheaths truncate or rounded 
Male flowers only in a spathe. 
. N. Schweinfurthit. 
. N. Welwitschii. 
oO. 
Anthers 1-celled : : : ‘ : = 6. Ne menor. 
Anthers 4-celled. 
Leaves fuleate : 2 : : . 7. N. horrida. 
Leaves not faleate . : : : : . 8. WN. interrupta. 
1, N. marina, Zinn., var. muricata, Al. Br. ex K. Schum. m 
Mart. Fl. Bras. iii. iti. 725, Stem thickly covered with spines. Leaves 
linear, with 14-20 patent triangular marginal teeth, which are generally 
longer than the blade is broad, and with about 5 on the back; sheaths 
rounded at the edges, each with 2 teeth on the edge, and 1-3 spines 
on the back.—Rendle in Trans. Linn. Soe. ser. 2, Bot. v. 397, 440. 
Nile Land. British East Africa : in the Albert Nyanza, Stuhlmann, 2841 (ex 
Rendle). 
2. N. graminea, Del: Fl. Hyypte, ii. 282, t. 50, fig. 3. Stems 
elongated, rooting at the lower nodes, from a few inches to 2 ft. long. 
Leaves linear, narrowing upwards, spreading-recurved, sometimes with 
a plumose habit, and other times lax and weak, with 36-40 teeth on 
the margins; sheaths elongated, with pointed lanceolate auricles, and 
8-10 teeth on the margin. Flowers in the axils sometimes female 
only, sometimes with a male and female side by side. Male perianths 
ending above the anthers in the ear-like lobes. Fruits solitary or 2-4 
together, narrow-oblong, or ellipsoid-oblong, tapering at the apex. 
Seed-testa marked with 25-30 regular lines of small areole.—Durand & 
Schinz, Conspect. Fl. Afr. v. 499; Kunth, Enum. iii. 115; Schweinf. 
Beitr. Fl. Aethiop. 194 and 292, 
Wile Land. Kordofan : Omkenem, near Arashkol Mountain, Steudzer, 213 
British East Africa: Jur; Kurshook Ali’s Seriba, Schweinfurth, 1217! Jur 
Ghattas, Schweinfurth, 2140 partly! Kinani, in the East Ongalea Mountains, 
‘Gregory ! 
Widely distributed in the Eastern Hemisphere. 
3. N. affinis, Rendle in Trans. Linn. Soc. ser. 2, Bot. v. 449: 
Stems slender. Leaves with 12-18 teeth on either margin, a quarter 
of the leaf-width in length; sheath irregularly broken on the upper 
margin and shoulders into short narrow outgrowths, tipped with spine 
cells, the outgrowths may extend almost to the base of the sheath. 
Female flowers apparently not quite mature. Spathe ellipsoid with a 
