208 
Found abundantly in portions of several 
fishponds open to the sea: Molii on Oahu 
Island; Ilae, Keawanui, Kupeke on Molokai 
Island. 
Widely distributed throughout tropical 
waters. It is one of the most frequently en¬ 
countered of shallow-water algae in the 
Hawaiian area. Tilden 401 (American 
Algae, Century V) in Herbarium University 
of California as Ceramium diaphanum is 
Centroceras clavulatum. This specimen is 
from the Hawaiian Islands. 
The structure of plants of this species is 
very variable, but the species is readily sepa¬ 
rated from the next (Ceramium) in being 
more brittle and usually larger, and in pos¬ 
sessing continuous corticating cells. 
It is listed from the Hawaiian Islands by 
PACIFIC SCIENCE, Vol. 1, October, 1947 
J. Agardh, Chamberlain, Setchell, Reed, 
and Rock, and, as Ceramium clavulatum C. 
Agardh, by Lemmermann and MacCaughey. 
Ceramium (Roth) Lyngbye, 1819: 117 
Ceramium is a large and complex genus. 
The limits of many of the species, especially 
the tropical ones, are as yet ill defined. Con¬ 
sequently, it seems best not to assign specific 
names to either of the following species, 
especially since not all necessary plants were 
found. 
Ceramium sp. (1) (see Fig. 10 a-b). 
Plants 4-8 cm. in height, dark pink to red, 
lying in soft tangled mats among other algae. 
Base of plants sometimes with rhizoids, the 
upper ends usually free. Branching irregu¬ 
larly dichotomous, with prominent forcipate 
Fig. 10. Ceramium sp. (1). A. Nodal region showing cortication. Scale C (divisions 10 microns). 
B. Tips of two plants, in the above figure showing forcipate nature. Scale C (divisions 10 microns). 
