THE MARINE BOTANIST. 179 



quent on rocks and the stems of L. digitata. An- 

 nual. Summer and autumn. 



RHODYMENIA CRISTATA.— TUFTED 

 RHODYMENIA. 



^^ Frond semicircular^ membranaceous, sub-dicho- 

 tomous, the segments somewhat dilated upwards, 

 repeatedly subdivided, the divisions alternate, de- 

 current, laciniate at the ends , tubercles spherical, 

 imbedded in the margin of the frond. Colour a 

 rose-red, nearly similar to that of Delesseria Alata." 

 — Grev, Alg. A northern species rarely found on 

 our shores. Parasitical on L. digitata. Annual. 

 July. Wick, Caithness. Frith of Forth. Berwick. 

 Shetland. Orkney. 



RHODYMENIA CILIATA.— FRINGED 

 RHODYMENIA. 



Frond shaped like a leaf, oblong, or lanceolate, 

 from two to four inches long, serrate or jagged at 



