272 BRITISH SEA-WEEDS. 



Cladophora Rudolphiana. Rudolphi's Clado- 

 phora. 



Fronds from a few inches to more than a foot long, very 

 slender, much branched, interwoven into flaccid, somewhat 

 gelatinous tufts of considerable length ; branches twice or 

 thrice forked or alternate, irregular ; branchlets long, comb- 

 like, secund, gradually tapered towards the tip ; cells many 

 times longer than broad ; those of the upper part of the 

 frond being shorter than those of the main stem, which are 

 sometimes swollen. 



This species grows on Zostera and sea-weeds in deep 

 water during summer, and is annual. It is very abund- 

 ant in certain localities on the coast of Ireland, and has 

 been found on other parts of our shores and in the 

 Adriatic. It adheres closely to paper, and preserves its 

 brilliant glossy green colour when dried. Some of the 

 cells of this plant are swollen in the middle, and on this 

 character Dr. Gray has founded a new genus, Cystothrix, 

 which he describes as follows : — "Frond erect, dichoto- 

 mously branched ; cells cylindrical, with a swollen one 

 before the furcation of the branchlets, filled with endo- 



Genus CXIII. CH51TOMORPHA. 



Frond a simple, hair-like, membranaceous or cartilagin- 

 ous filament, formed of oblong cells filled with granular 

 endochrome, the bottom cell larger than the others. — 

 Chjetomoepha, from the Greek chaite, flowing hair, and 

 morplie, form. 



This genus was founded by Kiitzing for the reception 

 of a portion of the species formerly included in the 

 genus Conferva. Some of the species of which it is com- 



