128 BRITISH SEA- WEEDS. \^Ielanos]ier7Tie{B. 



in having a more slender polished stem, much compressed 

 above when old, — a much narrower lamina, cuneate at the 

 base, and very long in proportion to the length of the stem, — 

 and the whole plant very dark in colour. In specimens of 

 average size the stem is eighteen to twenty-four inches long, 

 and the lamina of the same fiftv-four to sixtv inches. It is 

 described in Anderson^s ' Guide to the Highlands and 

 Islands of Scotland.'' " This, though rarely, is found on 

 the coast of Ayrshire. I have described a specimen of 

 Flustra menibranacea and Z. digitata as five feet in length 

 by eight inches in breadth. The plant must have been 

 L. Cloustoni. 



Family III. SPOEOCHXOIDE.^. 



" Je crains que la principale utilite que Ton doit retirer de cette etude se 

 trouve dans les gouts simples qu'elle inspire a ceux qui la cultivent. Le jcune 

 homme qui s'y applique avee ardeur, se derobe par son moycu aux passions 

 turbulcutcs du premier age, et fortilie sans cesse la saute par des exercices 

 agreables." — Vaucher. 



Genus IX. DES:MARESTIA, Lamour. 



Generic Character. Frond linear, cither filiform, compressed, 

 or flat, distichously branched, cellular, traversed by an internal, 

 single-tubed, jointed filament ; producing, when young, marginal 



