110 COMMON SEAWEEDS. 



This makes a very pretty specimen, though it dries 

 black, and does not adhere to paper. 



Cystoseiea GtEANULata. — The rough, knobby 

 stem, and more bushy appearance, will distinguish 

 it, as also its constant incrustation with zoophytes, 

 sponges, and molluscs. The air vessels are likewise 

 often two or three together, and the receptacles large. 

 Colour, clear olive green, or brown. 



SPHACELLAEIA. 



(The name is from a Greek "word, signifying " a gangrene," alluding to 

 the withered tops of the branches.) 



This plant, which has a rough, shaggy, olive or 

 brown mass of jointed and branched filaments, may 

 be recognized with a pocket lens. Observe the tips of 

 the branches — they are swollen into an oblong cell 

 containing a dark granular mass. This gives it a 

 withered look, and you will recognize Spliacellaria at 

 once 



There are two distinct classes. 1. Those whose 

 fronds are beset with woolly fibres at the base. 2. 

 Those whose stems are naked at the base. 



Sphacellaeia Scopaeia. — This is a fine bushy 

 plant, frequently found in lower-tide pools, and, as it 

 grows in deep water, is also thrown ashore after a 

 storm. 



Sphacellaeia Pltjmosa. — This is beautifully fea- 

 thered, dark, glossy, almost like the greenish black of 



