OF SOUTH AUSTRALIA. 
53 
C. pomoides J. Ag. is of a darker colour, and of denser structure so that 
the ball is firm and hard to the touch. The utricles are narrow, cylindrical, 
about 100 /x in diameter, and may be from 10 to 20 times as long. Each 
is constricted a little below the apex, giving a oapitulate appearance. The 
external membrane is thin, and but little thicker on the tip. Adult plants 
show an internal cavity filled with liquid. 
ft is found in South Australia, Victoria, and Tasmania. It is closely 
allied to C. bursa (L.) Ag. of European waters, and was looked upon by 
Harvey as identical with that species. 
C. mamillosum Harv. is of a lighter colour and looser texture, and the 
ball is soft to the touch. The utricles vary from cylindrical to clavate or 
pear-shaped, 1 mm. to 7 mm. long and from 400 /x to 2.5 mm. in diameter. 
The tips are rounded or flattened, and there may be a constriction below 
the apex. The membrane is thin but may be somewhat thickened over 
the tip. 
This species has a wider range than the preceding, being found in 
Western and South Australia and in western Victoria. It also occurs in 
Tasmania, New Zealand, and Japan, according to O. C. Schmidt. 
Since the utricles of C. mamillosum have four times the width of those 
of C. pomoides , the two species can be easily distinguished by the coarser 
pile of the former. 
Dichotomous Forms. 
These consist of erect, deep-green, many times forked, thickened fronds, 
attached by a somewhat expanded flattened base to the rocks on which 
they grow. They may reach a height of 30 cm., or even 60 cm. when growing 
in deep water, but are usually of less stature. They are sublittoral plants 
Fig. 35. — Utricles of Dichotomous Codiums; (a) C. galeatum ; 
(b) O. fragile ; (c) C. Muelleri. 
