W. WEST AND G. S. WEST: ALGA-FLORA OF YORKSHIRE. II9 



571. Dactylococcus bicaudatus A. Br. 



[Syn. Characium longipes Reinsch]. 

 N.W.— Cautley Spout. 



Var. exilis West & G. S. West. 

 S.W. — Horton Park, Bradford, forming a mucous, green 

 stratum on wet stones. 



Mid W. — I^angcliffe, near Settle. Ingleton. 

 N.W.— Cowgill Wold Moss, Widdale Fell, 

 Var. subramosum West & C.. S. West. 

 N. W, — Mossdale Moor, Widdale Fell, forming a green stratum 

 on dripping rocks. 



This variety is smaller than the type, and the cells are less 

 attenuated, concatenate and ramose. Diam. cell 3'8 — 6'5 /i. 



Genus SCENEDESMUS Meyen, 1829. 



572. Scenedesmus antennatus Breb. 

 Mil) W. — Langcliffe, near Settle. 



N.W.— Near Jervaulx Abbey. 



N.E.^ — Pilmoor,.near Thirsk. Scarborough Mere. 



S.E. — Skipwith Common. 



573. Scenedesmus obliquus (Turp.) Kiitz. 



[Syn. ^S". aattus Meyen]. 

 S.W.— Rawcliffe (H. F. Parsons). Heaton. 

 Mid W. — Markington ! (Rev. J. S. Tute). Bramhope (J. 

 Abbott). Adel. Arthington. Hawksworth. Wigton Moor. 

 Boston Spa. Malham Tarn. Arncliffe. Moughton Fell. 

 N.W. — Mickle and Cronkley Fells. Near Jervaulx Abbey. 

 N.E.— Near Rievaulx Abbey. Strensall ! (W. B. Turner). 

 Scarborough Mere. Scalby Beck. 



Var. dimorphus (Turp.) Rabenh. 

 S.E. — Skipwith Common. 



574- Scenedesmus bijugatus (Turp.) Kiitz. [Syn. S. 

 obtusus Meyen; S. qttadricauda (Turp.) Breb. var. 

 ecornis (Ehrenb.) Ralfs]. 

 S.W. — Rawcliffe (H. F. Parsons). Bradford. CuUingworth. 



