Marine Plants of Nha Trang — Dawson 
437 
i Fig. 48. a, Carpopeltis formosana: A portion of a regenerating plant, X 1.5. b, Gracilaria crassa: A mature cysto- 
!. carpic branch, X 2. c, Ceratodictyon spongiosum: A small part of a ramified clump, X l.d, Gracilaria sp.: Habit, X 2. 
^ e, Gracilaria eucheumoides: Part of a plant extracted from crevices in coral, showing several attachment discs on the 
[ fleshy segments, XI. 
Two Other collections are referred here with 
some question: 11380 from the back of a 
decorator crab, and 11076 from rocks at the 
edge of Cau Da wharf. These are alike and 
tetrasporic, but are low and different in habit 
from the usual forms of Hypnea esperi. They 
are similar in habit to Caulacanthus ustilatus 
Kiitz., but differ in structure. They seem to 
be like the plants B0rgesen figured (1924, 
figs. 27, 28) as Caulacanthus spinellus, but later 
(1950) called "a small Hypnea species.” 
Hypnea cervicornis J. Agardh 1852: 451 
(based on material from Brazil, West Indies, 
Mexico, and Mauritius); Okamura 1916, 
leones 4, pi. T59, figs. 6-9, pi. 160, figs. 
1-5; Tanaka 1941: 240, text fig. 13; Taylor 
1942: 104; Tseng 1936^: 45, pi. 5, fig. 24 
Fig. A6d 
LOCAL DISTRIBUTION: Forming a loose, in- 
tricate mass, on gravel and shell fragments 
in intertidal pools, Sta. 9 (11115, 11316); on 
rocks, Sta. 6 (11448). 
