54 
THE SEAWEEDS 
but may extend seawards to a depth of two or even more fathoms. They 
are firmly affixed to rocks or large stones, and give the appearance of slim 
green fingers floating in the water. There are at least four specific forms 
to be found on the South Australian coasts. 
KEY TO THE SPECIES. 
a. Fronds cylindrical terete. 
b. Tips flattened or rounded, vesiculose, the 
membrane not conspicuously thickened 
bb. Tips with a much thickened half-moon 
shaped cap 
bbb. Tips ending in a sharp or blunt point 
(mucro) 
aa. Fronds compressed, more or less flattened 
(tips flattened or rounded, as in C. 
Muelleri) 
C. Muelleri 
Kuetzing. 
C. galeatum 
J. Agardh. 
C. fragile 
(Suringar) Ileriot. 
C. decorticatum 
(Woodward) Howe. 
C odium Muelleri Kuetzing. 
Of varying height, stoutness and depth of colour. Utricles 2 or 3 times 
as long as broad, 600 /x to 1,200 p long by 180 p to 650 /x broad. 
Gametangia one-third to one-half as long as the utricles, 300 /x to 420 p 
long by 140 /x to 170 /x broad. 
Distributed round Australia, Tasmania, New Zealand, and the Sandwich 
Islands. The Indo-Pacific representative of the more specially Atlantic 
species, C. tomentosum (Hudson) Stackhouse. 
Codium galeatum J. Agardh. 
Usually tall, probably frequenting deeper water. Utricles 2 or 3 times 
as long as broad, 1,000 p to 1,500 p long by 350 p to 700 p broad. 
Gametangia about one-third to one-half as long as the utricle, 420 /x to 
480 /x long by 100 p to 180 p broad. 
So fai known from the south coast of Australia and from Kerguelen. 
Codium fragile (Suringar) Heriot. 
Usually coarser and of a dark green. Utricles 2 to 4 times as long as 
broad, 330 p to 1,500 p long by 100 p to 480 p broad. 
Gametangia one-third to one-half as long as the utricle, 170 /x to 450 p 
long by 50 /x to 170 p broad. 
