96 MARINE ALG 
Genus Corallina 
(“ Coral-like’’) 
C. officinalis, common coralline. Frond grows from a disk in tufts 
more or less dense. The plant is rigid, and seems like jointed, branched 
coral. The articulations are cylindrical at the base, wedge-shaped and 
flattened above. Branches emanate from the top of the articulations. 
The color varies from reddish-purple to gray-green, and is often bleached 
white when exposed to the sun. Common in tide-pools and on rocks 
at low-water mark from New York northward. (Plate XXXVII.) 
Genus Melobesia 
This genus will attract attention, although it cannot be gathered. 
It is a thin, brittle, scaly substance of indefinite form, which ex- 
pands horizontally and resembles a lichen. It forms brown and 
pink crusts on other algee and on rocks, stones, and shells. 
ORDER BANGIACEZE 
Genus Bangia 
B. fusco-purpurea (“brown-purple”). Fine, hair-like, unbranched, 
dark-purple filaments, one inch to six inches long. It grows in large 
patches on rocks and woodwork, floating free, but falling into soft, 
silky, fleece-like masses when left by the tide. Common on northern 
shores. (Plate XXXVII.) 
Genus Porphyra 
(“ Purple dye’) 
This plant, except in color, is like the green alga Ula. In 
color it is purple of various shades. The species are named from 
variations in the outline of the frond. They are found every- 
where, and throughout the year. The plants are edible, being 
the laver of commerce, eaten principally by the Chinese, who 
make them into soup. 
P. vulgaris. Frond a broad, thin membrane of purple color, three 
ie rete eens a) margin much waved; sometimes attached at 
e center, often widely expanded and folded, sometimes deeply lobed. 
(Plate XXXVIL) ; ae 
P. laciniata. Differs from P. vulgaris in being divided into narrow 
segments or into wavy, ribbon-like forms. (Plate XXXVIL.) 
