HELMINTHOCLADI^. 15 7 



Helminthora divaricata. The divaricate Hel- 

 minthora. 



Fronds densely tufted, thread-like, pale red ; stem simple 

 or forked; branches opposite or alternate, horizontal, much 

 divided ; branchlets numerous, divaricate, scattered, obtuse. 

 Spores on club-shaped threads, embedded in the frond ; 

 tetraspores unknown. 



This plant is annual, and grows on stones and sea- 

 weeds during summer and autumn, at and beyond low- 

 water mark. It is widely distributed in the northern 

 latitudes of America and Europe, and is found in many 

 places on the coasts of Great Britain. 



Genus LXIV. NEMALION. 



Frond cylindrical, gelatinous, elastic, forked, composed of 

 filaments set in gelatine ; those of the axis simple, longitu- 

 dinal, closely twisted into a cord-like column, surrounded 

 by other oblique, communicating filaments, from which issue 

 the horizontal, necklace-like, fastigiate, forked filaments of 

 the outer part of the frond, or periphery. Spore-threads 

 club-shaped, embedded in the outer filaments of the frond ; 

 tetraspores, according to Agardh, " formed in the terminal 

 cells of the peripheric filaments, triangularly divided, with 

 prominent sporules." — Nemalio^, from the Greek nema, a 

 thread, and leion, a crop. 



Nemalion multifidum. The many-cut Nexnaliou. 



Fronds worm-like, six to ten inches long, as thick as a 

 crow's quill, or thicker, of a dull purple colour, forked near 

 the base, and repeatedly at long intervals upwards ; root an 

 expanded fleshy disc. Spore-threads embedded in the frond ; 

 tetraspores formed in the terminal cellules of the outer 

 filaments. 



