THE LIFE OF THE SEA-SHORE 



141 



THE LAURENTIA. 



Masses of stony-looking, white- 

 jointed twigs are often verv 

 abundant in pools at the base of 

 the limestone cliffs. This growth 

 is the so-called Coralline, which 

 has nothing to do with the corals, 

 as its name seems to imply, but 

 is really a curious seaweed with an 

 outer coating of carbonate of 

 lime. The plant secretes this 

 stony covering as it grows, the 

 vegetable tissues forming a slender 

 stem within. If a dried tuft be 

 held in a flame, it will be seen to 

 ])urn with a fine white light. By 

 }:)]acing a specimen in weak acid, 

 the lime will be dissolved, so 

 that the structure of the plant 

 can be seen. 



One of the treasures of the 

 half-tide pools is the Peacock's- 

 tail Seaweed. It is a most 

 remarkable - looking, fan - shaped 

 weed, with graceful fronds ex- 

 panding in almost perfect half- 



ten inches in length, with a main 

 stem or trunk and a multitude of 

 smaller branches, like a miniature 

 tree. On the shady side of the 

 pool, growing from three to six 

 inches in length, with slightly- 

 forked branches of a fine deep 

 crimson colour, is the Griffithsia, 

 named after Mrs. Griffiths, who 

 has discovered and described so 

 many of our native seaweeds. If 

 we take a specimen home, and 

 throw it into fresh water, the 

 membrane will burst with a crack- 

 ling noise, and the beautiful 

 colour be discharged. 



The Laurentia, named after 

 the French naturalist, M. de la 

 Lauriencia, is a rather interesting 

 weed with a wide shore distribu- 

 tion from extreme high-water 

 mark to beyond low-water mark. 

 It has a flatfish frond, and un- 

 divided main stem, from which 

 grow out stout branches alter- 

 nately clothed with lesser branches. 

 This weed has rather a hot, biting 

 taste, and was formerly eaten in 

 Scotland, where it was known as 

 "pepper dulse." 



THK KNTEKOMOKl'llA 



