Marine Plants of Nha Trang — DAWSON 
411 
Axes without numerous small branchlets, 
or at least these not equally distributed 
on all sides. Gelidiella 
55. Lower parts uniseriate; growth intercalary 
Goniotrichum 
Lower parts not uniseriate; growth not 
intercalary 5 6 
56. Thallus hollow, with regular transverse 
diaphragms Champia 
Thallus not hollow, or at least without 
diaphragms 57 
57. Growing with and resembling a sponge 
Ceratodictyon 
Not as above 58 
58. Creeping on mangrove roots; constricted 
as if jointed Catenella 
Not as above 59 
59. Thallus in transection showing a medulla 
of loosely interlaced filaments 60 
Medulla without loosely interlaced fila- 
ments 61 
60. Thalli caespitose, the segments arching 
Gigartina 
Thalli not caespitose, erect Grateloupia 
61. Branching dichotomous 62 
Branching not dichotomous 63 
62. Segments to 3 mm. wide, with -f — 
frequent proliferous branchlets ........ 
Carpopeltis 
Segments under 2.5 mm. wide, without 
frequent proliferous branchlets 
. . . .^. Gymnogongrus 
63. Axes 250 n or less in diameter 64 
Axes mostly 1 mm. in diameter or more 
... 65 
64. Tetrasporangia and antheridia borne in 
swollen, terminal stichidia.Gelidiopsis 
Not as above Wurdemannia 
65. Cystocarps with nutritive filaments ex- 
tending from gonimoblast to pericarp. . 
Gracilaria 
Cystocarps without special nutritive fil- 
aments Gracilariopsis 
c d e 
Fig. 23. a, Asterocystis ornata: Part of a filament 17-20 
/i in diameter, X 73. b, c, Goniotrichum humphreyi: b. 
Upper portion of a filament, X 185; c, basal portion 
of a filament, X 233. <7, e, Erythrotrichia parietalis: d. 
Lower portion of filament showing penetrating basal 
cell and thick, swollen wall at the base, X 600; e, upper 
portion of a filament showing parietal chromatophores. 
X 350. 
Asterocystis ornata (Ag.) Hamel 1924: 451, 
fig. 7b-e; Tanaka 1952: 11, fig. 6. Conferva 
ornata C. Agardh 1824: 104 (Europe) 
Fig. 23^ 
LOCAL DISTRIBUTION: A minute epiphyte 
on various small algae such as Tolypiocladia 
from Sta. 4 (11156a) and Wurdemannia from 
Sta. 2 (11185). 
