FUCUS VESICULOSUS. 97 



Ireland, where the means of livelihood are scanty, should 

 have ceased to yield a profitable return ; but these are 

 revolutions to which all manufactures are subject. At 

 some future time other uses may be found for the 

 abundant crop of these plants which our shores supply. 

 At present large quantities come into use, either in 

 the state of ashes, or in a fermented state, as a valuable 

 manure for green crops. Their value as manure is said 

 to be enhanced in districts most removed from the sea ', 

 and this may not be merely on the principle that " cows 

 afar off have long horns," but the mineral substances 

 they contain may be less abundant in the soils of inland 

 districts than in those nearer the coast, to which the 

 spray of the sea must carry a considerable quantity of 

 these salts. 



None of our common Fuci are known beyond the 

 waters of the Atlantic except F. vesiculosvis, whicli 

 occurs in the Mediterranean Sea, and again in the 

 Pacific, on the western shore of North America. This 

 species, indeed, is the most patient of the family in 

 enduring a great variety of conditions. As to climate, it 

 submits to the frozen rigour of the Arctic circle, and to 

 the tropical fervour of the Canary Islands. In the latter 

 country, however, it appears to be on the very verge of 

 extinction, the fronds being reduced to the smallest 

 compass, consisting of little more than the root and the 

 fructification ; just as we see annuals grown in a poor 

 and dry soil frequently dwindle to a pair of leaves and a 

 flower, and these of the smallest size. Comparing the 

 specimens from the Canary Islands with those grown in 

 deep water in the North of Europe, we find so much 



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