OF SOUTH AUSTRALIA. 
165 
formed of bundles of spore threads radiating from a central basal placenta. 
Tetrasporangia immersed among the peripheric cells of the marginal pro- 
cesses. Seen from the surface under the microscope the large cells appear 
each surrounded by a fosette of the small cortical cells, “rosulate- areolate.” 
Fig. 37 . — Rhodophyllis volans : a, plant; b, plant 
in fruit; c, section through a con- 
ceptacle; d, section of the frond; 
e, portion of the surface of the 
frond, with scattered tetraspores; f , 
some tetraspores, removed. (After 
Harvey.) 
A. — Inner cells in two layers, parallel to the surface of the frond. The 
cortical small cells disposed in a circle round the inner, 
a. Fronds without veins. 
Rhodophyllis volans Harvey. 
Fronds tufted, 5 cm. to 10 cm. long, flabelliform-multipartite, the 
segments from 6 mm. to 12 mm. broad, eystocarps scattered over 
the disc of the frond. Tetrasporangia in the pinnae, zonately 
divided. 
Western Australia, South Australia (Investigator Strait, Eastern 
Bays), Victoria. 
