POTAMOPHTLA, R. Br. 
Spikelets laterally sli^'htly compressed, on short or rather long pedicels, 
])anicled ; rhachilla jointed above the I'udiinentary basal glumes. Florets 3 ; lower 
2 reduced to minute empty valves, up])ermost hermaphi-odite f>r unisexual with the 
organs of the other sex reduced. 
Glumes reduced to very miiuite rounded or truncate scales, or to an obscure, 
entire or bilobed hyaline rim. Em])ty valves very small, hyaline, nerveless, 
subulate or elliptic and rounded or loi)ed ; fertile valve meml)ranous, r)-nerved, 
awnless, nerves raised, sometimes slightly winged. Pale ;'-nerved ; otherwise 
similar to tlie fertile valve. Lodicules 2, finely nerved. Stamens fi. Styles 
distinct ; stigmas feathery. Orain obovate, compressed, crowned by the thickened 
bases of the styles, enclosed by the unaltered glume and pale, free. 
Piather tall a(juatic grasses, blades flat ; ligules membranous ; panicle effuse or 
contracted. 
Species 3, L In South Africa, 1 in Madagascar, and f in New South Wales. 
PLATE 444. 
POTAMOPHILA PREHENSILIS, Beuth. {V\. (*ap., Vol. \]\.. p. 059). 
Nat. Order Graminea'. 
Stems several feet high, branclied, many-noded, slightly compressed or terete, 
glabrous, smooth ; internodes up to 4 inches long ; branches spreading at a I'igiit 
angle or almost so ; leaf-sheaths rather tight, shorter than or as long as the inter- 
nodes, sliglitly compressed and more or less keeled, strongly striate, scabrid in the 
iippermost part of the keel, hairy near themoutli or glabrous, except the sometimes 
minutely villous nodes ; ligule membranous, oblong or truncate. ^ to 1 line long, 
pubescent ; blades linear-lanceolate from a very short contracted base, acute, 3 to 
5 inches bv 3 to 6 lines, ilat, flaccid, glaucous, s])aringly hairy and minutely scabrid 
on both sides, margins and midrib very rough from minute reversed spines ; 
primar}^ nerves 3 to 4 on each side. 
Panicle terminal, 4 to (> inches long, open, very lax, rigid ; branches spi'eading, 
fine, up to 4 inclies long, the lowest usually paired, sparingly branched, compressed 
and angular, scaberulous or smooth below, branchlets 2-3-spiculate ; pedicels 1 to 
7 lines long. 
Spikelets lanceolate-oblong, acute, 3 to 4 lines long, slightly twisted, |)allid. 
Glumes extremely minute truncate hyaline scales. Valves, empty one 
subulate, ^ to | Vme long, nerveless ; fertile valve tightly clasping the similar pale 
with tlie inflexed margins, norves raised, slightly winged, scaberulous. Lodicules 
ovate ; anthers 3 lines long ; styles ^ line long ; stigma exserted near the l)ase of 
the valve, 1 to 1^ line long. Grain unknown. 
HdbitRt : Natal. Near the mouth of the Umzimkulu Pviver, in copses and 
woods, Drege ; Umbilo waterfall, liehiDaiui, 8156; Umpumuh^ to 2000 feet, 
connuon in bush, liuchauait 288 ; Inanda, Wood 1305. 
Drawn from Buchanan's 288. 
Fig 1, A glumo : 2 and .'). empty valves; 4, fertile valve ; 5, pale; 6, pistil, stamens 
and lodicules. All cnlarcjcd. 
