ON THE NOTHE LEDGES. 195 



nipt wall or quay, wliich protects a tiny mimic bay. 

 This little indentation is a most prolific source of 

 washed sea-weeds in the summer and autumn, and 

 many specimens of rarity and teauty are gathered 

 here. The rich and brilliant Rliodymenia laciniata is 

 not uncommon, and the more delicate and scarcely 

 less beautiful NitopJiyllum punctatum [see Plate V.), 

 with Delesseria sanguinea and sinuosa, and many other 

 species equally attractive, occur. Some of these are, it 

 is true, deep-water kinds, washed in by the tides ; the 

 first named, for example, I have never met with in a 

 growing state ; but this little bay is particularly rich 

 in littoral species. At the bottom of the wall or 

 quay-like edge grow several fine tufts of those very 

 elegant Algae, Griffithsia coralUna, and G, setacea ; 

 Ceramium echionotum [see Plate VI.) and C. cih'atum, 

 exquisite plants for microscopic study, are also scat- 

 tered about in the lowest levels, though not often 

 uncovered ; and the fissures which penetrate the stone 

 are well fringed with Delesseria alata, Dasya coccinea^ 

 Chylocladia articulata, Ptilota plumosa, and other 

 shade-loving species, that grow in dense mossy tufts. 

 The only living specimen that I found at Weymouth 

 of Delesseria sanguinea, was growing in one of these 

 clefts, where also small and brightly-coloured speci- 

 mens of Pyllopliora ruhens occur; — a plant which 

 is obtained much more abundantly, and of far greater 

 dimensions, by the dredge. This is an Alga of much 

 value for the Aquarium. It is elegant in form and 

 colour ; it bears confinement perfectly, and throws off 

 a large quantity of oxygen; besides which it is 

 almost always studded with multitudes of parasitic 



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