RJiodoinelece.'] polysiphonia. 295 



Hab. Torquay, Mrs. Griffiths ; Appin, Capt. Carmicliael. 

 Extremely rare. A good figure of it is given by Dr. 

 Greville in Ins ' Cryptogamic Flora.'' 



5. POLYSIPHONIA NIGEESCENS, GveVllle. 



. Hab. On rocks, &c., in the sea. Perennial. Summer. 

 Tronds tufted, and from six to eight inches high ; fila- 

 ments robust, rigid, and generally rough below, with broken 

 branches, much branched and bushy above; articulations 

 short, capsules ovate; colour dark-brown, becoming black 

 in drying. In a young state it is often very beautifully tufted, 

 and of a purplish-pink colour, which it retains in drying. 



6. POLYSIPHONIA FUECELLATA, Hai'Vey. 



This is a very rare species. Mrs. Griffiths found it 

 floating in th^ sea at Sidmouth. It was obtained also by 

 Mr. M^Calla near Carrickfergus in 1846. It is between 

 PolysipJionia fastigiata and Folysijphonia nigrescenSf but 

 different from both. See Phyc. Brit., PI. vii. 



7. POLYSIPHONIA PASTIGIATA, GrevllU, 



Hab. On Fiwus nodosus and F. vesiculosiis, especially 

 the former, forming globose, dense bushy tufts, of a brown 

 or at times a yellowish colour. It is very common ; but, 

 common as it is, I have a liking for it, as it was the first of 

 the small Algse I knew by name. I had been correspond- 

 ing with Professor John Pleming, of Edinburgh, jespecting 



