96 FLOWERLESS PLANTS 



tion. So far as the scheme of nutrition is 

 concerned they are capable of nothing more 

 than is accompUshed by the leaf-hke expansion. 

 It is important to bear these points in mind 

 when studjdng such plants as seaweeds, for the 

 terms " leaf," " stem," and " root " are often 

 useful for descriptive purposes, although they 

 must not be taken in a strictly botanical sense. 

 There are not a large number of green sea- 

 weeds which attract a great deal of attention. 

 The Ulvas (Sea Lettuces) have already been 

 mentioned. Of this group there are two or 

 three species which are commonly found. These 

 are popularly kno\Mi under the name of 

 Laver, in company with some of the Red Sea- 

 weeds such as those in the genus Porphyra. 

 The latter are generally spoken of as Purple 

 Laver. Nearl}^ all these plants are said to be 

 good to eat, and indeed are largely consumed 

 in some districts, though it must be admitted 

 that the taste for the delicacy is an acquired 

 one. The Ulvas are often a very attractive 

 feature in the pools which the receding tide 

 leaves behind. All the green Sea Lettuces 

 seem to flourish exceedingly wherever the 

 water is in an impure state owing to drainage 



