OLIVE-GREEN AND BROWN SEAWEEDS 65 
E. siliculosus. Tufts loosely entangled at the base, free and feathery 
above, of indefinite length; spores in pod-like forms at the ends of the 
branches. Common on the larger alge and on wharves. 
E. viridis. Tufts a little more loose and expanding than in E. silicu- 
losus; spores in pods at the base of the branches. (Plate IX.) 
£. tomentosus. Fine filaments, densely interwoven into rope-like, 
spongy masses, two to four inches long; yellowish-brown; pods on stalks. 
Found in summer growing on F'ucus. 
ORDER SPHACELARIACER 
Genus Sphacelaria 
S. cirrhosa. Olive-brown; branched, feathery filaments, one half of 
an inch to two inches long. Each branch ends with an oblong, swollen cell 
containing a dark granular mass which gives it a withered appearance. 
These cells can be seen with a strong pocket-lens. It forms dense, globe- 
like tufts on Fucus. 
S. radicans. Filaments one half of an inch to one inch high; branches 
few and hairy. It forms a dense, grass-like covering, of indefinite extent, 
on the under side of muddy rocks. Found on the New England coast. 
Genus Cladostephus 
C. verticillatus. Fronds bristle-like, dividing regularly; covered 
with whorls of branchlets set close to the stems, each whorl overlapping 
the previous one, giving the plant a spongy appearance. (Plate IX.) 
ORDER RALFSIACEE 
Genus Ralfsia 
The species of this genus are brown, leathery, crustaceous 
expansions of indefinite form, one inch to six inches in diameter, 
resembling lichens. They appear on rocks in shallow, exposed 
pools. 
ORDER ENCELIACEE 
Genus Punctaria 
Dotted-weeds. Fronds pale olive-green, membranaceous, leaf- 
like, with short stem; covered with spores which appear like dots. 
P. latifolia. Frond pale green, four to twelve inches long, one inch to 
five inches wide, leaf-like, and tapering suddenly to a short stalk; much 
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