430 
PACIFIC SCIENCE, VoL VIII, October, 1954 
Amphiroa foliacea Lamouroux 1824: 628, 
pi. 93, figs. 2, 3 (Mariannas Islands); 
Weber van Bosse and Foslie 1904: 92, pi. 
14, figs. 1-11 
LOCAL DISTRIBUTION: In loose clumps 
among other algae on coral rocks, Sta. 1 
(11133). 
Amphiroa fragilissima (L.) Lamouroux 
1816: 298; Weber van Bosse and Foslie 
1904: 89, pi. 16, figs. 1, 2, 5; B0rgesen 
1934: 7. Corallina fragilissima Linnaeus 
1767: 1305 (Caribbean Sea) 
Fig. 40g, h 
LOCAL DISTRIBUTION: In drift, Sta. 11 
(11356); in drift, Sta. 3 (11098); Sta. 4 
(11188). 
These specimens are variable in diameter, 
in nodal swelling, and in the angle of branch- 
ing, but seem to fall within the limits of var- 
iability of this widespread species. 
Key to the Species of Jania 
1. Terminal segments broad, ungulate, at 
least in part J. ungulata f. brevior 
Terminal segments not broad 2 
2. Segments mostly under 125 /x in diameter 
J. capillacea 
Segments over 130 /x in diameter. ...... 3 
3. Angle of branching wide; segments 2.5-6 
diameters long . J. decussato-dichotoma 
Angle of branching narrow; segments 6- 
12 diameters long J. longiarthra 
Jania ungulata f. brevior (Yendo) 1905: 38. 
Corallina ungulata f. brevior Yendo 1902: 
27, pi. 3, fig. 9, ph 7, fig. 9 (Boshyu Prov., 
Fig. 40. 
LOCAL DISTRIBUTION : Forming small clumps 
5-8 mm. high on a sponge from Sta. 9 
(11317). 
The segments are 130-220 fx in diameter. 
Jania decussato-dichotoma (Yendo) Yen- 
do 1905: 37; Dawson 1953: 117, pL 27, 
fig. 3. Corallina decussato-dichotoma Yendo 
1902: 25, pL 3, figs. 1-3, pi. 7, figs. 3, 4 
Fig. 40/ 
LOCAL DISTRIBUTION: Forming dense little 
clumps about 1 cm. high among other algae, 
Sta. 4 (11182). 
These decussately branched plants have 
segments 130-180 /x in diameter and 2.5-6 
diameters long. They are in good agreement 
both with Yendo's illustrations and with spec- 
imens from Pacific Mexico. 
Fig. 41. a, b, Jania capillacea: a, A small portion of 
a plant of 11100 with relatively slender branches, X 10; 
b, a small portion of a relatively coarse plant of 11250 
with segments 125 /x in diameter, X 10. 
