RHODOPHYCE®H, OR FLORIDEA 211 
constrictions, or rugose markings. There are no 
foliar expansions, and the branching is dichotomous. 
Galaxaura lapidescens forms hard stony tufts of dense 
branches of almost as indurated a character as the 
Corallines. 
The genus Choreocolax is one of the most remark- 
Fia 63.—a, Chetangium ornatum slightly reduced; b, young carpogonial 
branch of Seinaia furcellata highly magnified. (b, after Schmitz.) 
able among Algze, since it contains at least one 
species (though it certainly shows a remarkable 
resemblance to Harveyella) that is wholly parasitic, 
viz., Ch. albus on Rhodomela subfusca. It has no 
chromatophores, and subsists entirely at the expense 
of its host-plant, so far as is known a unique 
P2 
