W. WEST AND G. S. WEST : ALGA-FLORA OF YORKSHIRE. 49 



Mid W. — Markington, with zygospores ! (Rev. J. S. Tute). 

 Askwith (W. B. Turner). Baildon. Eldwick. Adel Bog. 

 Rombald's Moor. Farnley. Leathley. Near Norwood Hall, 

 above Lindley Reservoir. Malham Tarn. Moughton Fell. 

 Wigton Moor. 



N.W.— Mickle Fell. 



N.E. — Gormire ; Strensall ! (W. B. Turner). Pilmoor, near 

 Thirsk. Terrington. 



S.E. — Riccall and Skipwith Commons. Hornsea Mere. 



A form with a distinctly granulate membrane was observed 

 from Skipwith Common ; the granules were large, but of slight 

 elevation. 



193. Closterium Pseudodianse Roy. 



Mid W. — Roundhay Park, Leeds (vii. 1898). Cocket Moss, 

 near Giggleswick (iv. 1898). 



194. Closterium parvulum Nag. 

 Generally distributed throughout the county. 



S.W. — Doncaster. Ogden Clough. Wibsey (with zygospores). 

 Cullingworth. Bingley. Keighley Tarn, and near Keighley 

 (with zygospores). 



Mid W. — Adel. Wigton Moor. Eldwick. Baildon Moor. 

 Boston Spa. Cocket Moss, near Giggleswick. Ingleton. 

 Ribblehead. Harrogate. Staveley Dam, near Knaresborough. 



N.W.— Mickle Fell. Great Shunnor Fell. Lund's Fell. 



N.E. — Strensall. Pilmoor, near Thirsk (with zygospores). 

 Terrington. Near Scarborough. Levisham. Hayburn Wyke. 



S.E. — Riccall Common. 

 Var. angustum var. nov. 



Smaller than the typical form and considerably narrower. 



Diam. 77 /x; apices 94-102/* apart. 



N.E. — Pilmoor, near Thirsk. 



195. Closterium arcuatum Breb. 

 S.E. — Skipwith Common. 



196. Closterium Jenheri Ralfs. 



S.W. —Wakefield (W. H. Dikes). Cullingworth. 



