66 



BNTEROMORPHA. 



and altogether a prettier plant. It grows in a 

 radiating manner from a very broad disc. This 

 plant is represented on plate c, fig. 2. 



But the most useful of the Chlorosperms 

 may be found almost at the very margin of 

 high water, where they live rather more in the 

 open air than under water. These are the Ulvce 

 and EnteromorphcB, the first being known by the 

 popular title of Laver, and the second of Sea- 

 grass. There is another plant that is also called 

 Sea-grass j but it is not an alga, and will be men- 

 tioned at the end of this chapter. 



The Common Sea-grass {Enteromorpha com- 

 pressa) may be seen in abundance on the stones 

 and rocks that are even for a few hours sub- 

 merged daily. The leaf, or rather frond, of this 

 species is variable in width, sometimes being 

 hardly wider than common sewing thread, and 

 sometimes so wide as to resemble a very narrow 

 ulva. It is this variety which is represented 

 in the engraving, plate c, fig. 3. When the 

 waves retire, leaving sundry pools fringed with 

 this and other sea-weeds, their fronds form 

 hiding-places for innumerable living beings of 

 very many species; and by gathering masses of 

 the wet weed into a basket, and then putting it 

 into a lai'ge vessel filled with sea-water, myriads 



