HALF AN HOUR WITH SEA-WORMS. 81 



visible, and its foot-tubercles and bristles (seize) 

 enable it to crawl along with some rapidity, and to 

 swim with even greater ease. The gills are arranged 

 in tufts on the back and sides. Distantly allied to 

 this species is the Eunice gigantea, whose greater 

 length and different colour enable you at once to 

 distinguish it. Very often the latter species numbers 

 over four hundred segments, and is four feet long. 

 Its gills are well developed and large, and its mouth 

 is armed with seven or eight rather formidable horny 

 jaws. Polynoe is another kind of sea-worm, which 

 you may find by turning over any flat stone between 

 the tide ranges. It is about an inch and a half in 

 length, of a brown colour, and is rather an insignificant 

 looking object. When you examine it more carefully, 

 you perceive that its back is covered with a series of 

 very thin plates which overlap each other. Far more 

 attractive creatures are the two species of Phyllodoce, 

 so called on account of the " leaf-shaped " organs on 

 their backs, by means of which they swim. One of 

 these, Phyllodoce viridis, is, as its name signifies, of 

 a bright grass-green colour. Seek out a place near* 

 low water where the young mussels are attached to the 

 rocks in great numbers, and you will hardly fail to 

 see this pretty worm, which can scarcely be distin- 

 guished sometimes from a thin strip of seaweed. 

 Its length is only about three inches ; but in the 

 other species, P. laminosa, it frequently extends to 

 a foot, and includes two or three hundred segments. 

 The latter is even more striking, when carefully 



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