SEAWEEDS. 293 



In the lower series of tide-pools, a tufted weed attracts the 

 sight by reason of its brilliant iridescence, which often causes 

 it to be plucked from its native pool, only to be thrown back 

 again, for on emergence from the water all the beautiful play 

 of colour has gone. It does not appear to have any common 

 name, but to give it a chance of being popularly known, let us 

 call it the Rainbow Bladder- weed (Cystoseira ericoides). The 

 many branches of its frond are full of little bladders, whence 

 its scientific name (Kystos, a bladder ; sezra, a cord), and it gets 

 its specific title of ericoides from its habit somewhat resembling 

 that of the Heath-plant (Erica). A tuft pulled up and care- 

 fully overhauled will afford the zoologist a number of diverse 

 forms of life. Several species of Crustacea make it their home, 

 and the leaf- worms hide themselves in the centre of the little 

 bush. Mollusks, sponges, and ascidians are there also, and 

 the description of the animal inhabitants of such a tuft would 

 make a fair chapter. 



All the species of seaweeds to which we have already 

 referred, are members of the class Fucaceae. We have now 

 to take a glance at other brown and olive weeds, some of which 

 are the giants of the tribe, but which belong properly to the 

 deeper waters, though every gale will make us well acquainted 

 with their forms heaped up upon the shore. In this class 

 known to botanists as the Phaeosporeae the reproduction is 

 generally of a lower type than in those we have been consider- 

 ing. In the majority of forms there is no sexual process, the 

 species being reproduced, as a rule, by zoospores, which are 

 somewhat similar to the antherozoids of Fucus. They are 

 produced in special cells, the contents of which break up into 

 a number of these zoospores, which escape through a pore, 

 and germinate. 



Getting down into a drang at extreme low spring-tide, we 

 shall find the rocks to seaward covered with Tangle (Lam- 

 inaria digitatd), whose huge round stems clasp the rocks with 

 their claw-like false-roots. The leafy portion is broad, of a 



