G. AMPHIROA. 
135 
RIGID. 
1. Amphiroa rigida. Branching ; branches dis- 
persed and few in number ; articulations cylindrical, 
nearly touching each other, and wrinkled ; colour 
greyish white ; height about three centimetres. — 
Plate 11. fig. 1. 
Mediterranean. 
SHINING. 
2. Amphiroa lucida. Branches dichotomous ; 
articulations perfectly cylindrical and shining; colour 
white ; height from four to six centimetres ; diameter 
of the articulation one millemetre. 
SPINDLE-SHAPED. 
3. Amphiroa fusoides . Dichotomous; articula- 
tions spindle-shaped, the lower ones warty ; colour, a 
brilliant white ; height from four to six centimetres ; 
diameter of the stem and lower branches from one to 
two millemetres.— Plate 11. fig. 2. 
Indian Ocean. 
BRITTLE. 
4. Amphiroa fragilissima . Nearly dichotomous; 
branches hair-like ; articulations cylindrical, with a 
swelling in the form of a ball or pad at their extre- 
mities. 
Mediterranean, Indian and American seas. 
DE GAILLON’S. 
5. Amphiroa Gaillonii . Dichotomous; articula- 
tions long and cylindrical, a little swelled at the ex- 
tremities ; those at the summits slightly compressed ; 
surface sometimes warty ; beautifully coloured with 
