3G COMMON SEAWEEDS. 



high-water mark, and seldom if ever grows below half- 

 tide. 



It grows indeed where the spray of the tide just 

 reaches it, and seems to require exposure to the air for 

 many hours a day. True, it becomes black and crisp 

 under the fierce rays of a midsummer sun, but upon 

 immersion in the up-coming tide it regains life and 

 flexibility. The furrow in its stem, its having no air 

 vessels, and the dense or thick tufts from two to six 

 inches high, will sufficiently distinguish this from its 

 robust brother, 



Fuctts INTodosits, which floats out on the water 

 without a mid-rib also, but buoyed up by large air 

 vessels placed singly in the stem, which varies from 

 two to four or six feet in length. The frond is 

 jagged ; and the fruit, which is olive green or yellow, 

 according to its contents, is an oblong pod upon a 

 stalk set always in a tooth of the frond. 



Observe, the vesicles or air cells are in the very sub- 

 stance of the frond, and sometimes as much as two 

 inches long : boys in Scotland make whistles of them 

 by cutting them across near the end. This is quite 

 the largest British species of Fuci, rigid, tough, and 

 in thick tufts ; but, like all seaweeds, its growth and 

 appearance depend upon it position. I cannot too 

 much impress upon young seaweed gatherers this 

 important and often tiresome fact, that a plant may 

 be short and bushy in high-tide pools, and long, strong, 

 and thin at low- water mark; even the very colour 

 changes as it lives more in the richer soil of the deep 

 sea. It is really the same difference that we find 



