Fig. 184. RHODYMENIA CRISTATA. 



Colour. A rose-red; becoming scarlet in fresh water. 

 Suhstance. Membranaceous. 



Character of Frond. Flat; narrow; ribless; repeatedly divided in a forked manner 

 from the base. General outline fan-shaped or round (the figure fails to give 

 this.) Divisions widening upwards; many times sub-divided; lesser ones 

 alternate, occasionally jagged at the ends. 



Measurement. British specimens rarely above an inch high. 



Fructification. Of two kinds. 1. A mass of spores in little spherical dark-red 

 capsules, half the size of poppy-seed; imbedded in tlie upper margins. 2. 

 Tetraspores imbedded in the thickened and darkened tips. 



Halitat. Orkney and Shetland Islands. ♦Frith of Forth. Berwick-upon-Tweed, and 

 a few more places in the north. Thrown ashore; sometimes on the stems of 

 Lam. digitata. Very rare indeed. 



Now Eutliora crisfata. Six specimens w^ero found at Berwick in 1853. 



Fig. 185. NITOPHYLLUM BONNEMAISONIA. 



Colour. Bright rose-red. 



Substance. Delicately membranaceous. Very thin. 



Character of Frond. A flat, ribless expansion, rising from a short stalk; slit and 

 deeply divided. General outline fan-shaped or round. Divisions broadly 

 wedge-shaped; about equal in length; overlapping each other. Veins rising 

 from the base, and spreading faintly upwards. 



Measurement. From 2 to 4 inches high, and about as broad. 



Fructification. Of two kinds. 1. A mass of spores in largish round capsules, 

 scattered over the surface. 2. Tetraspores in roundish groups (sori); scattered 

 over the surface. 



Hahitat. Orkney, Bute, Ilfracombe, Torquay, Miltown Malbay, &c. On the stems 

 of Lam. digitata. Kare. 



Fig. 186. GRATELOUPIA FILICINA. 



Colour. Dull pinkish-purple; discolouring green. 

 Suhstance. Membranaceous. 



Character of Frond. Flat; narrow; tufted; wavily branched. Stems simple or ouce 

 forked; tapering to each end; naked at base; above, set with long, opposite 

 or alternate, wide-spreading, wavy, flat branches. Branches either simple or 

 clothed in the upper part with branchlets; all tapering to each end. 



Measurement. British specimens seldom more than 2 inches high. 



Fructification. Of two kinds. 1. Spores in minute globular capsules; immersed in 

 the substance of the branches. 2. Tetraspores imbedded in the branchlets. 



Habitat. South of England. On submarine rocks at half-tide level; frequently where 

 a small streamlet runs into the sea. Very rare. 



A^ery like some forms of Gelidiuui cornemn ; but much softer. 



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