Plate LXXIV. 
Fig. 346. PORPHYRA VULGARIS. 
Colour. Bright purple ; almost rosy when dry ; very glossy. 
Substance, Delicately membranaceous ; very thin. 
Character of Frond. A flat, narrow, ribless, leafy expansion, with a pointed end. Quite 
simple ; but the margins becoming more or less strongly waved and plaited as the 
plant grows. 
Measurement. From an inch to 1 or 2 feet long. Not more than 3 inches wide, and young 
specimens mere threads. 
Fructification. Minute seeds {zoospores) formed of the colouring matter in the cells of which 
the frond-membrane is composed (four in each cell) ; and in due time dropping out. 
Habitat. Our coasts generally. On rocks, &e. between tide-marks ; from high-water mark 
downwards. 
It is almost “past a perad venture” that this plant is but a different condition of the pre- 
ceding one, Porphyra laciniata (see last Plate). The narrowest of the specimens in Fig. 346 
are found in winter or early spring covering the rocks near high-water mark with their tiny, 
purplish-pink, satiny fronds. Later in the season, the larger, frilled form abounds in the 
same locality, as also lower on the shore, where it may he found mixed with the broad divided 
fronds of P. laciniata. All are gathered indiscriminately for the table. P. vulgaris is rarely 
so dull coloured and greenish as P. laciniata often is ; but, on the other hand, P. laciniata is 
sometimes as bright as the other ever is. And intermediate instances both in form and colour 
are met with. Dr. Harvey unites the species in his Nereis Boreali- Americana, under the 
name laciniata. 
Fig. 347. BANGIA FUSCO-PURPUREA. 
Colour. Blackisb-purple ; occasionally greenish ; glossy. 
Substance. Tenacious ; soft ; sticky. 
Character of Frond. Tufts of hair-like threads {filaments) ; forming a close-clinging, dark 
purple or greenish layer upon rocks. Filaments straight or slightly curled ; 
undivided ; unbranched ; tubular ; containing rows of minute colour-cells radiating 
from the centre. 
Measurement. Filaments, several inches long ; their width variable ; narrow ones containing 
only one colour-cell ; others from 2 up to 5 ; these forming (with the intervals) a 
tesselated line across (see Figure for magnified appearance of this strictly microscopic 
object). 
Fructification. Minute seeds {zoospores) formed of the colour-cells in the filaments (one to 
each cell) ; and in due time dropping out. 
Habitat. Our coasts generally, and in fresh-water rivers and canals. On rocks, wood, &c. 
near high-water mark. Not uncommon. 
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