OF SOUTH AUSTRALIA. 
251 
bb. Pericentral siphons 5, corticated with large 
cells gradually decreasing in size outwards, 
c. Ramuli dwarf, ecorticate to axils of most 
larger branches, densely caespitose. 
Ramuli pointed, spirally disposed M as chalo stroma 
Schmitz. 
cc. Lateral ramuli short, spine-like, spirally dis- 
posed. 
Sporangia nidulating in hollows of short 
ramuli Acanthopliora 
Lamour. 
aa. Segments cylindrical or plane, destitute of spines, 
sterile parts extensive, lax, sometimes full of 
hyphae. 
d. Axis polysiphonous, sterile parts lax for a 
long time, or rather tubulose-hollow, 
median axis giving off verticillate 
branches. 
e. Segments terete, mostly articulate- 
constricted, branching on all sides 
(apparently verticillate) Coeloclonium 
J. Ag. 
ee. Segments terete or compressed-terete, 
stipitate, slightly contracted Dolichos celis 
J. Ag. 
dd. Axis polysiphonous, sterile parts lax but 
soon becoming compact, always packed 
with percurrent hyphae. Segments 
cylindrical or complanate, branching on 
all sides, distichous or plane Chondria (Ag.) 
Harv. 
CLADURUS Falkenberg. 
Frond compressed or terete, dendroid, pinnate, transversely striate, corti- 
cated; the axis articulated, composed of a circle of large oblong cells 
surrounding a central cell ; the periphery of several rows of small, angular 
(mostly) coloured cells. Cystocarps ovate, containing a tuft of pear-shaped 
spores. Stichidea containing tripartite tetrasporangia. 
Cladurus elatus (Sond.) Falkenberg. 
= Rytiphcea elata Harvey. 
Holdfast or attachment a large bulbous disc. Frond 60 cm. or more in 
height, the stem and larger branches 4 mm. to 6 mm. in diameter, the 
secondary branches 1 mm. to 2 mm., excessively branched and bushy or 
dendroid. Stem simple or forked, or irregularly divided; its divisions 
supporting decompound di-trichotomous, or alternately divided heads of 
branches. Lateral branches 15 cm. to 20 cm. long, sometimes laxly, some- 
times very densely ramuliferous ; the ramuli either scattered or fasciculate, 
