BY THE SEASIDE— PLANT LIFE 



cated in structure, in fact they appear to be pos- 

 sessed of stems and leaves, but we shall return to 

 them in a moment. 



Most of the common red Algae are so delicate in 

 structure that they require a fairly high magnifica- 

 tion for their examination. The thin, membranous 

 fronds of the beautiful crimson Delessera Sanguinea, 

 may be sought below low tide limit or may be found 

 washed up upon the shore. Superficially the plant 

 resembles a red hart's-tongue fern, with much more 

 delicate fronds than ever fern of that species pos- 

 sessed. We may well compare its structure with 

 that of the sea lettuce, for it is equally transparent. 



In the rock pools of many parts of the coast we 

 may happen upon a most curious almost white sea 

 weed, known as Coralline or Corallina Officinalis. 

 Its branched, feathery stems are hard and stony and 

 the whole plant bears a superficial resemblance to 

 a coral, hence its name. The plant absorbs a sub- 

 stance known as calcium carbonate from the sea 

 water and deposits it in the form of a hard, stony 

 covering over its surface. Calcium carbonate does 

 not occur in sea water everywhere, at least not in 

 sufficient quantity to be of use to the Coralline, that 

 is the reason the sea weed is not quite so common 

 as some of the others we have mentioned. The 

 curious armour-plating of this sea dweller, should 

 be studied under the microscope. 



The chief scientific interest of the sea weeds, 

 however, lies in their mode of increase, it is so 

 totally different from that of any of the higher 



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