W. WEST AND G. S. WEST : ALGA-FLORA OF YORKSHIRE. 149 

 Gf,nus OSCILLATORIA Vauch., 1803. 



737. Oscillatoria princeps Vauch., 1803. 

 Mid W. — Malham Tarn Bog ; very fine, Aug. 1896. ■ 

 N.E. — Pilmoor, near Thirsk; vii. 1898. 



738. Oscillatoria limosa Ag., 18 12. 



[Syn. Oscillaria Fr«lichii Kiitz., 1843]. 



S.W. —Bradford. Dewsbury. Frizinghall. Wibsey. Farnley. 



Mid W. — Wetherby (F. A. Lees). Baildon. Wigton Moor. 

 Malham. Moughton Fell. Penyghent. Pond at Pool. 

 Holden Gill, near Keighley. Eldwick. Boston Spa. Staveley 

 Dam, near Knaresborough. Ilkley. 



N.W. — Masham. Near Moorcock Inn. Great Shunnor Fell. 

 Mickle Fell. Dodd Fell. 



N.E. — Strensali. Scarborough Mere. Hayburn Wyke. 

 Stokesley. 



S.E.— Waghen. Beverley. Routh. Loftsome Bridge, near 

 Wressle. Newsholme, near Howden. 



739. Oscillatoria irrigua Kiitz., 1843. 



This species frequently forms dark purple velvety patches 

 over which the water runs quickly. 



S.W. — Keighley. Farnley. Near Halifax. 



Mid W. — Addingham. Arthington. Baildon. Oughtershaw 

 Moss. 



N.W. — River Ure. Duerley Beck near Hawes. Sedbergh. 



740. Oscillatoria tenuis Ag., 1813. 



[Syn. Oscillaria tenuis var. viridis Kiitz., 1849]. 

 S.W. —Wakefield. Bradford. Frizinghall. Halifax. 

 Mid W. — Sherburn. Baildon. Leeds. Pond at Pool. 

 Staveley Dam, near Knaresborough. Ilkley. 

 N.W.— Sedbergh. Mickle Fell. 

 N.E. — Seamer. Malton. 



741. Oscillatoria amphibia Ag., 1827. 



[Syn. Oscillaria tenerrima Kiitz., 1843]. 

 S.W. — Bradford. Frizinghall. Kildwick. Doncaster. 



Bot. 5-J 



