SEA-WEEDS. 107 



On every part of the shores we may find that 

 common marine plant the Podded Halidrys 

 (Halidrys siliquosa], which lies in dark branched 

 masses about the beach, or grows on the rocks 

 and stones upon it. It has the common name of 

 sea-tree, from its shrub-like appearance, and it 

 may be known by its numerous pods, about an 

 inch long, which grow on both sides of the stem 

 and branches. It is of a pale olive-green, but 

 turns quite black in drying. In Norway this plant, 

 as well as the knobbed fucus, is called Knoptang. 



On many parts of the coast, the Strap-shaped 

 Himanthalia, or Sea Thongs (Himanthalia lorea), 

 attracts the notice of those who are interested in 

 the productions of the ocean. Sometimes we may 

 look for it in vain for weeks on the beach, but 

 after a storm it will lie in great profusion, and 

 hundreds of specimens might be collected in an 

 hour's walk. It is commonly on our coast called 

 Sea Thongs, and this name well describes it. It 

 is a flat olive-green sea-weed, often ten feet long, 

 and sometimes found in Cornwall of the length of 

 twenty feet, looking like a continuation of flat 

 narrow pods or seed-vessels, dividing every now 

 and then into two branches, each of which divides 

 farther on into two more, and so on through its 

 whole length. When in a perfect state, however, 

 it has one peculiarity by which it may at once be 

 known from all our other sea-weeds. It springs 

 from a kind of cup at its base, and in the earliest 

 stage of its growth these cups may be seen thickly 

 scattered on the rocks in the sea, and looking just 

 like those plants of the fungus tribe which are 

 called Pezizas. Little projections arise from this 

 hollow cup, after it has grown into a good size 



