OCEAN LIFE, 



ALGM. 



THE Sea-weeds belong to the cellular order of vegetables, and 

 to the Cryptogamic class of the Linnaean system. The term 

 Algae, is applied to a vast class of aquatic plants, many of which 

 are inhabitants of fresh water. Eut the highest forms are those 

 popularly termed Sea-weeds. 



" The root among the Algae is rarely much developed. They 

 do not, in a general way, derive nourishment from the soil on 

 which they grow. We find them growing indifferently on rocks 

 of various mineralogical character, on floating timber, on' shells, 

 on iron, or other metal, on each other in fine, on any substance 

 which is long submerged, and which affords a foothold. Into 

 none of those substances do they emit roots, nor do we find that 

 they cause their decay, or appropriate to themselves the consti- 

 tuents of these substances. They are nourished by the water 

 that surrounds them, and the various substances which are dis- 

 solved in it." 



" On whatever substance the Algae may feed, it is rarely ob- 

 tained through the intervention of a root. Dissolved in the water 

 that bathes the whole frond, the food is imbibed equally through 

 all the cells of the surface, and passes from cell to cell toward 

 those parts that are more actively assimilating, or growing more 

 rapidly. The root, when such an organ exists, is a mere hold- 

 fast, intended to keep the plant fixed to a base, and prevent its 

 being driven about by the action of the waves. It is ordinarily 

 a simple disc or conical expansion of the base of the stem, 

 strongly applied and firmly adhering to the substance on which 

 the Algae grows. This is the usual form among all the smaller 

 growing kinds. When, however, as in the gigantic Oar-weeds, 

 the frond attains a large size, offering a proportionate resistance 

 to the waves, the central disc is strengthened by lateral hold- 

 fasts or discs formed at the bases of side roots emitted by the 

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