18 2 
THE SEAWEEDS 
NIZYMENIA Sonder. 
Frond horny -membranous, fiat, linear or strap-shaped, decompound, 
branches distichous, above more regularly, oppositely pinnate, composed of 
three strata, the medullary of densely woven, anastomosing filaments, the 
intermediate of roundish-angular cells, the cortical of minute coloured cells. 
No central tube. Cystocarps sessile, thick-walled, wrinkled, containing 
minute sub-seriated spores, radiating from a central, basal fibro-cellular 
placenta. Tetrasporangia not known. 
Nizymenia australis Sonder. 
Fronds 15 cm. to 30 cm. high, 3 mm. to 6 mm. wide. Main branches much 
constricted at the insertion. Segments obtuse. Colour blood-red. 
South Australia (Eastern Bays), Victoria, Tasmania. 
Fig. 50 . — Nizymenia australis: a, plant; b, part 
of small branch, with conceptacles ; 
c, transverse section of the frond; 
d, vertical section of a conceptacle. 
(After Harvey.) 
