150 
THE SEAWEEDS 
Gigartina disticha Sonder. 
Frond compressed, thick, fleshy, linear, with a few erect main branches 
and distichous pinnules. Cystocarps said to be solitary in the tips of the 
pinnules. Sori elongate immersed in the pinnules. Height 20 cm. to 30 cm., 
width 4 mm. to 5 mm. Colour a livid-purple. 
Western and South Australia (Encounter Bay, Investigator Strait, 
Eastern Bays). 
Fig. 22.— Gigartina disticha : a, plant; b, cross-section, 
to show the structure of frond, and an 
immersed sorus of tetraspores; c, tetra- 
spores. (After Harvey.) 
