OF SOUTH AUSTRALIA. 
67 
Receptacles in alternate stipitate clusters of 2-3, each subtended by a bract; 
each receptacle 2 to 4 nun. long, thickened upwards, blunt, three-ridged, 
the ridges toothed. 
King George’s Sound, Western Australia; Holdfast (Glenelg) and 
Guichen Bays, South Australia. Turner described ft from a specimen 
picked up by R. Brown at the mouth of the Tamar, Tasmania. 
Sargassum biforme Sonder. 
Common caulis short rounded, rachides of the branches acutely tri- 
quetrous, branchlets reflexed. Leaves emerging from a flat surface of the 
rachis, the lowest lanceolate oblong, much undulate crisped toothed on the 
margin, to 10 cm. long and 2.5 cm. broad; upper leaves lanceolate-linear 
serrate, bracteoles of the panicle very narrow. Vesicles large, subspherical 
crowned by a mucro or leaflet. Receptacles prismatic oblong, acute angled, 
the margins toothed 
Western Australia; Le Fevre Peninsula (Port Adelaide), South Australia. 
Subgenus Eusargassum J. Agardh. 
A short common caulis bears several elongated branching fronds. Leaves 
simple, usually midribbed, with conspicuous cryptostomata (glandules). 
Vesicles spherical, mutic, on longer or shorter petioles. Receptacles more or 
less compound, smooth or toothed according to the Subdivisions, and 
arranged in cymes, panicle^ or racemes. 
The most typical subgenus, of world-wide distribution and including 
about 140 described species of which 47 are Australian. In Australia they 
abound in the warmer waters of the north, replacing Arxtirophycus pre- 
dominant in the south. To this subgenus belongs the floating Sargassum 
of the Sargasso Seas of the Atlantic and North Pacific, but it does not 
occur in Australia. 
Only three species have so far been recorded from South Australia, and 
it is therefore convenient here to omit the general classification of the sub- 
genus and to give some account of these three species. 
Sargassum crist at um J. Agardh. 
Stems of fronds slender, like twine, smooth. Leaves lanceolate-linear, 
rather pointed, midribbed, with conspicuous scattered cryptostomata, 
serrate at the edges; the basal leaves 3 to 4 cm\. long and to 8 to 9 mm. 
wide, the upper much shorter and narrower. Vesicles when adult mutic, 
about the size of a peppercorn, borne on a petiole as long as their diameter. 
Receptacles, junior compressed, mature rounded-cylindrical, thickened in 
the middle, and with each margin ending in a winged fimbriated crest. 
Western Australia and South Australia. 
