202 ALG. [CHAP. 
with a motley collection of star-fishes, sea-urchins, 
mussels, and the remarkable clusters of eggs of the 
whelk and cuttlefishes? Here, too, it is we find 
those strange eggs of the dog-fish—Mermaids’ 
purses as they are popularly 
called, as though such superior 
beings as the Mer-folk would be 
troubled with such things as 
purses! We do not believe they 
are possessed of pockets wherein 
to keep them if they had them. 
But you recollect the seaweeds? 
First of all there is that tough, 
brownish species with narrow- 
branching fronds studded here 
and there—chiefly where the frond 
branches out—with air-bladders, 
which children are fond of ex- 
ploding by pressure between 
finger and thumb. This is the 
Bladder Wrack or Fucus vesicu- 
losus, and is most common on all 
rocky shores, covering as it does 
great areas of low rocks along the 
shore. We have painful recollec- 
tions of this species. Not in- 
Bic. 151. Fucus nodesus, frequently have we, in hurrying 
over the wrack-covered rocks, 
elated with some choice find, slipped on the fronds 
of this plant and been hurled flat on our back on 
the rugged, uneven surface of the rocks. The office 
of the bladders is, of course, to give buoyancy to the 
