CORALLINACEiE. 131 



southern and western coasts, and in Ireland ; but as it 

 grows in deep water, and is too heavy to be easily- 

 thrown up by the waves, good specimens can only be 

 obtained by dredging. In some places the fronds cover 

 a large extent of the sandy bottom of the sea — not at- 

 taching themselves, but lying heaped together, strata 

 above strata, only those on the surface being alive. 



Melobesia fasciculata. The fasciculate Melobesia. 



Fronds formed of uniform, oblong cells, free, coral-like ; 

 branches short, cylindrical or flattened, crowded together, 

 their tips truncated, broad, and somewhat concave. 



In mode of growth, and some other respects, this spe- 

 cies resembles the last, but may be distinguished from 

 it by the form of the tips of the branches. It is of a 

 pale purple colour when fresh, and fades to a dirty 

 white when drying. 



Melobesia polymorpha. The many-shaped 

 Melobesia. 



Fronds formed of uniform, oblong cells about twice as 

 long as they are broad, thick, stony, closely attached to 

 and encrusting rocks, occasionally rising into short, thick, 

 clumsy branches. Spore-conceptacles minute, extremely 

 numerous. 



This species is very common all round our coasts. It 

 grows both in deep and shallow water, and varies in 

 colour accordingly : in the former it is of a dark-purple, 

 while in the latter it is usually of a milky- white. 



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