OF SOUTH AUSTRALIA. 
419 
naked gonidia, which are developed directly from a vegetative cell or by 
the division of a vegetative cell; development in the higher forms by 
the fusion of sperms and eggs; sperms very minute, eggs large; zygote, 
following meiosis, dividing directly into four to eight spores; germinating 
spores producing monoecious or dioecious gametophytes. 
Family BANG1ACEAE (Zanardini) Berthold 1882. 
Gonidia arising by division or developing directly from an originally 
vegetative mother cell (gonidangium) ; in special monogonidangia, cut off 
by a curved wall in a vegetative cell. 
Porphyra C. Agardh. Bangia Lyngbye. Wildmama De Toni. 
Subclass EUFLORIDEAE De-Toni 1897. 
Morphological alternation of similar generations shown or inferred to be 
present, the plants being either male and female gametophytes or sporo- 
phytes; in most of the higher forms at least, the sporophytic generation 
having its origin in the zygote, which in conjunction with one or more 
auxiliary cells remains as a parasite on the female gametophyte, diploid 
carpogonidia being produced within a cystocarp ; carpogonidia, upon ger- 
mination, building up the sporophytic plant, which in turn bears quartets 
of haploid spores (tetraspores) ; protoplasmic continuity between cells as 
a rule. ' 
Order NEMALIONALES Oltmanns 1904. 
Plants filamentous, the uniseriate filaments creeping or erect, or stouter 
and corticate, when developing relatively soft branches with either the 
central filament or the multiaxial type of structure ; cells uninucleate, with 
axial or lateral chromatophores and with intercellular connections ; asexual 
reproduction by monosporangia, very exceptionally by bi- or tetrasporangia ; 
sexual reproduction by spermatia in spermatangia formed from the surface 
vegetative cells and carpogonia with elongated trichogynes borne on few- 
celled carpogenic branches; the zygote itself producing the carpospores 
after meiosis either directly or after establishing connections with nutritive 
cells on the carpogenic branch. 
This order includes marine algae, purely fresh-water forms, and certain 
species able to endure either salt or fresh water. 
Family CHANTRANS1ACEAE Kylin 1928. 
Plants small, filamentous, with apical growth and a more or less evident 
erect or prostrate axis ; cell arrangement uniseriate, the cells uninucleate, 
with one or more chromatophores; asexual reproduction by mono-, bi-, or 
tetrasporangia, formed laterally or terminally ; sexual reproduction by 
small-branched spermatangial filaments producing spermatia and by carpo- 
genic branches of one to three cells, the cystocarps small, with carpospores 
formed in sparingly branched filaments. 
