482 - POLYGONACES (Wright). | Emew. 
Katanari Reaion : Griqualand West ; Asbestos Mountains at the Kloof Village, 
Burchell, 1687 ! 
Eastern Recion: Natal; without precise locality, Cooper, 1216 ! 
Also in Australia. 
This species differs from Z. spinosa, Campd., in the larger, less rugose outer 
fruiting perianth with longer spinescent segments, and the inner erect segments 
being broader and more rounded. 
~Orver CXIII. PODOSTEMACEZA&. 
(By A. W. Hitt.) 
Flowers regular, hermaphrodite or diccious. Perianth inferior, 
membranous, 3—5-partite or represented by minute scales or entirely 
absent, Stamens hypogynous, 1 to many ; filaments free or united ; 
anthers oblong, 2-celled, dehiscing longitudinally ; pollen 1—2-celled. 
Ovary sessile or stipitate, 1-3-celled ; styles 2—3 ; stigmas capitate 
or decurrent ; placentas axile or parietal ; ovules many, anatropous. 
Capsule 1-3-celled, dehiscing by valves, often septifragal. Seeds 
yest minute, sessile, exalbuminous ; cotyledons flat ; radicle very 
short, 
Submerged herbs of various habit, often resembling mosses, foliaceous and 
frondose hepaticze and algie ; flowers minute, variously arranged. 
Distris. Species about 130, chiefly in the tropics and subtropics of the 
Southern hemisphere. 
I. Tristicha.— Flowers hermaphrodite. Perianth equally 3-partite. 
Il, Spherothylax.—Flowers hermaphrodite. Perianth of 2 small linear 
segments. 
Ill. Hydrostachys.—Flowers diwcious. Perianth none. 
I, TRISTICHA, Thouars. 
Flowers hermaphrodite. Perianth membranous, 3-partite ; seg- 
ments oblong, obtuse, slightly imbricate. Stamen 1, hypogynous ; 
filament long ; anthers oblong. Ovary oblong, 3-celled ; styles 3, 
short, linear ; stigmas decurrent on the inner side of the styles; 
placentas axile; ovules numerous. Capsule oblong, crustaceous, 
septicidally and septifragally 3-valved. 
_ Herbs with a moss-like habit, growing under water and attached to rocks by 
a flat-lobed thallus ; stem slender, much-branched, Leaves small, sessile, entire, 
pellucid, 1-nerved. Flowers terminal or axillary ; pedicels stiffly erect, each with 
3 bracts at the base. 
Disrris. Species 3, variable and difficult of limitation. 
Also in Tropical Africa, the Mascarene Islands and Tropical America. 
1. T. hypnoides (Spreng. Syst. iv. Cur. Post. 10) ; stems czspitose, 
often very short, branched, more or less compressed ; leaves broadly 
