320 
THE SEAWEEDS 
spreading. This primary frond emits an annual crop of deciduous, slender, 
glabrous branches, 20 cm. to 50 cm. long, and either simple or emitting 
laterally from a main branch or rachis, several similar, long, simple 
branches. The branches of either series are generally denuded at the base, 
and closely pinnated above with horizontal pinnae, which are from 1 cm. to 
3 cm. long, and older ones becoming pinnulate. Both pinnae and pinnulae 
are clothed with very slender, dichotomous, rose-red, soft ramuli. The 
cystocarps ovate, much inflated, with a prominent orifice ; the spore- 
filament is excessively branched, resembling a miniature tree, loaded with 
innumerable pear-shaped spores, and nearly fills up the cavity of the 
pericarp. The stichidia are of small size and clustered. The colour, when 
quite fresh, is a beautiful clear rosy-red or crimson, but old specimens are 
frequently brownish-red. The substance of the primary stem is rigid, that 
of the branches very soft and flaccid. The plant adheres closely to paper. 
South Australia (Holdfast Bay, Eastern Bays), West Australia, 
Tasmania. 
H.eterosiphoviia struthiopenna (J. Ag.) De Toni. 
= Dasya phmigera Harvey. 
Frond 7-12 cm. long, stem for 2 cm. to 5 cm. lightly hirsute and coarse, 
compressed ; ramuli irregularly pinnate, at the apices almost areolate, 
corticate, the lower pinnae of the ramuli are in tangled masses, the middle 
ones longer, branched and squarrose; ramelli secund, subdistichous, with 
very dense dichotomous pinnae, which are divaricate, entangled, mono- 
siphonous. Six to seven central siphons. Cystocarps large, on the short 
ends of the polysiphonous ramelli. Bright red; adheres to paper. (Very 
similar to II. Muelleri.) 
West Australia (King George Sound). 
TIAPLODASYA Falkenberg. 
Frond parasitic, erect, terete, dorsiventral ; stem clavate, sympodial; the 
secondary ramuli developed spirally on the sympodial axis; four central 
cells ; the rhizoids are corticate. Cystocarps large, arranged spirally on the 
principal sympodial axis. Stichidia developed at the apices of the young 
ramuli, in the short lateral sympodia, numerous, dorsiventral, pedicellate, 
subarcuate. Tetrasporangia in a longitudinal row on the convex side. 
Antheridia arranged as tetrasporangia. 
Haplodasya Reinboldii Falkenberg. 
Frond dwarf, less than 3-4 mm. high. The only species, with the 
characters of the genus. 
South Australia. 
HALODICTYON Zanardini. 
Frond a tubular (simple or forked) network, formed by numerous 
inosculating, confervoid filaments; the meshes irregular, emitting at the 
angles free, horizontal ramelli. Cystocarps urceolate, containing a tuft of 
pyriform carpospores. Stichidia lanceolate, containing a single or double 
row of tetraspores. 
