BY THE SEASIDE— PLANT LIFE 



food is absorbed from the sea water over the whole 

 of their surface. 



We may well begin our study of the seaweeds 

 with an examination of the external structure of as 

 many different kinds as we can find. Some of them 

 are flattened and very thin forms and of them the 

 Sea Lettuce may be taken as typical. This plant, 

 known to scientists as Ulva Lactuca, occurs at high- 

 water mark. In its fully developed form it is pale 

 green and so thin as to be almost transparent; its 

 structure may be studied under the microscope 

 without difficulty. Then there is the very common, 

 green, Compressed Enteromorpha which grows in 

 great profusion on the rocks of the shore, rendering 

 them exceedingly slippery. The closely related 

 Intestinal Enteromorpha as it floats in the water 

 resembles a green, membranous tube and those of 

 us who have ever done any zoological dissection will 

 appreciate how well named this plant is. The struc- 

 ture of both the Enteromorphas can easily be seen. 

 Many of the brown and red Algse will provide us 

 with a good deal of occupation in making out their 

 structure. Some of them, the brown Ectocarpus 

 Siliculosus for example, may be found, growing in 

 moss like tufts, which are usually attached to one 

 of the larger Algae living between the tide marks. 

 It is one of the simplest of the brown sea weeds, 

 consisting of branched threads, but one cell in 

 thickness. The Wracks, of which the Common 

 Bladder Wrack or Pop weed with its little air filled 

 bladders is familiar to everyone, are more compli- 



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