OF SOUTH AUSTRALIA. 
95 
j Ecklonia radiata (Turn.) J. Agardh. 
Stipes 8 to 50 cm. long, to 1 cm. thick, having beneath the cortex a circle 
of muciferous lacunae; lamina to 8 cm. long, the apex decaying, the median 
part to 8 cm. wide, with numerous linear pinnae, narrowed at base and 
apex, the upper ones to 55 cm. long, all armed at the margin with 
triangular spines. In harbour forms the surface is smooth, in ocean forms 
(var. exasperata) the surface is prickly with spines similar to those of the 
margins. 
All Southern Australia, Tasmania, New Zealand. 
Ecklonia lanciloka Sonder. 
Stipes slender, lamina elongate bearing horizontal linear-lanceolate 
pinnae, undivided with spinose-dentate margins. 
Rivoli Bay (F. v. Mueller). 
MACROCYSTIS C. Agardh. 
The giant among the Kelps, and indeed of all plants, the stems growing 
to hundreds of feet in length. Attached by a much branched holdfast with 
a sucking disk at the end of each branch. The cylindrical stems come off 
from the upper part of the base, at first a little branched, then simple 
spreading in long trails through the water. The plants are caespitose and 
form submarine forests or thickets. The long stems bear leaves formed by 
the splitting of a broad primary terminal leaf, and developed in one-sided 
(secund) order along the lengthening stem. Each leaf with a petiole, 
inflated above into an elongated vesicle and bearing at its apex a long 
simple often plicate-rugose flattened lamina. The terminal growing 
segment of the stem splits at the base into a succession of leaves with petiole 
and vesicle below and lamina above. The splitting continues upward till 
the leaves are freed. Each lamina tapers at base and apex, and is bordered 
with rather distant cilia. The structure of the stem shows a thin cortex, 
an intermediate zone hollowed out into muciferous lacunae, and a medulla 
of stouter and slenderer filaments intermixed. The sporangia occur in 
submerged leaves near the holdfast, forming spots or sori of varying form; 
they are accompanied by unicellular club-sliaped paraphyses. 
Mucrocystis pyrifera (Turn.) Agardh. 
Stem, as observed in Australia, 9 to 80 metres long, slender, to 4 mm. in 
diameter, bearing leaves on one side, spaced at distances of from 5 to 30 
cm., 60 to 120 cm. long and 5 to 7.5 cm. wide, undulate-furrowed. Vesicles 
ultimately 10 to 13 cm. long. From whatever depth the plants vegetate, 
