HANDBOOK OF SEA-WEEDS. ig 



ferns. All the Sphacelarioe are easily recognized by the 

 withered appearance of the tips of the fruiting branches. My- 

 riotrichia is a genus of small parasitical plants, the two British 

 species of which grow chiefly on the sea thongs (Chorda). 



The Chordarise are sometimes gelatinous in structure, in other 

 cases cartilaginous. The fruit is contained in the substance of 

 the frond. The genus Chordaria consists of plants which 

 have the appearance of dark coloured twine. There are two 

 British species, one being rather common. Chorda filum, sea- 

 rope, another string-like seaweed, grows in tufts from a few 

 inches to many feet in length, and tapering at the roots to about 

 the thickness of a pig's bristle. In quiet land-locked bays with 



Fig. ii. Padina pavonia. 



a sandy or muddy bottom, it sometimes extends to forty feet in 

 length, forming extensive meadows, obstructing the passage of 

 boats, and endangering the lives of swimmers entangled in its 

 slimy cords, whence probably its other name of " dead men's 

 lines." 



The Mesogloiere in a fresh state resemble bundles of green, 

 slimy worms. There are three British species, two of which 

 are not uncommon. Although so unattractive in external as- 

 pect, they, like many others of the same description, prove very 

 interesting under the microscope. One of the cartilaginous 

 species, Leathsia tuberiformis, has the appearance, when grow- 

 ing, of a mass of distorted tubers. 



