BY THE SEASIDE— PLANT LIFE 



velopment than Fungi, to which Bacteria, Yeast, 

 Mould, etc., belong, though they are not so highly 

 developed as Ferns and not nearly so advanced as 

 flowering plants. A very short acquaintance with 

 'Algx will show us that they are either green, 

 brown or red. The green Algx are nearly all fresh 

 water forms, though a few are to be found 

 in the sea; on the other hand brown and red 

 'Alg3e are common in the sea and rare in fresh 

 water. 



As we study our seaweeds on the shore, if we are 

 really observant, we shall notice that they live in 

 zones or belts according to their colour. There are 

 exceptions to this rule but, in general, the green 

 seaweeds dwell in situations where they are only 

 covered by the sea at high tide; the red seaweeds 

 are to be found mostly where they are always below 

 water and, between the two, the brown seaweeds 

 occur. In some parts, this colour scheme is very 

 striking. Frequently red seaweeds may be found 

 above high- water mark it is true, but in such cases 

 they nearly always occur in rock pools and they are 

 invariably sheltered by brown seaweeds. 



In our chapter on plant life we mentioned that 

 many coloured plants contained the green colouring 

 matter, chlorophyll, just as do the ordinary green 

 leaves. We showed too that by boiling some green 

 leaves in methylated spirits we could extract the 



chlorophyll and that its solution had the peculiar 

 property of appearing green when light passes 

 through it and red when light is reflected from it. 



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