OF SOUTH AUSTRALIA. 
135 
bands, globose, formed of dichotomous threads radiating from a centre, 
bearing carpospores in the terminal joints. Tetrasporangia cruciately 
divided. 
Galaxaura dolicarthra J. Agardh. 
A handsome plant, 10 cm. or more in height and spread, densely-branched, 
regularly forked, or ternate, corymbose, at first pink then whitening. Frond 
in bold joints separated by stipitate supports. Calcareous crust firm. 
From West to East along southern Australia from Geraldton to Sydney. 
Family GELIDIACEAE. 
Frond terete or compressed, laterally branched, with a distinct articulated 
central tube, showing a filamentous structure. Gonimoblast consisting of a 
clump of spreading filaments, often confluent with special auxiliary ceils 
of the thallus, the apices of the fertile filaments confluent in a membrane 
from which the carpospores arise. Tetrasporangia variously divided. 
There are two sub-families of the Australian forms, which are in marked 
contrast in contours and in structure; the Wrangelieae comprising the 
genus Wrangelia, and the Gelideae containing the closely related genera 
Gelidium and Pterocladici. 
WRANGELIA C. Agardh. 
Frond erect, terete-filiform with a conspicuous monosiphonous articu- 
lated axis with long joints, naked or covered with a cortex, decompound 
branching, verticillately ramellose at the nodes. Cystocarps terminal at the 
apex of a ramulus, involucrated by a whorl of ramelli, and consisting of a 
tuft of naked pear-shaped pedicellate spores and slender paranemata. Tetra- 
sporangia borne on the sides of whorled ramelli, globose, with a hyaline 
envelope, triangularly divided. Of the 24 named species 20 are Australian ; 
thus Australia is the headquarters of this beautiful genus. They are all 
found in the temperate seas of the south. Already seven species have been 
recorded for South Australia, and others may well be anticipated. 
A. — Armatae. 
Ramuli of the verticils rather rigid, more or less diverging, mucronate 
with a sharp terminal joint. 
a. Fronds from the base articulate, ecorticate. 
Wrangelia nitella Harvey. 
The slenderest species, frond flaccid, pellucidly jointed through- 
out, decompound pinnate, branches mostly opposite, with whorled 
ramelli at the nodes. Ramelli di-trichotomously multifid, divisions 
very patent and very acute. Tetrasporangia globose, sessile on the 
ramelli. Height 5 cm. to 9 cm., colour a clear, deep, crimson-lake. 
Western Australia. 
Wrangelia mucronata Harvey. 
Stiffer and harsher than the preceding, the verticils spaced 
apart, but closely appressed. The ramelli once trichotomous, the 
