W. WEST AND O. S. WEST : ALGA-PLOUA OF YORKSHIRE. 1 73 



853. Navicula Dirhyncus Ehrenb. 

 S.W.— Moiley. 



Mid W. — Add Bog. Malliam Tarn. 

 S.E. — Near .Sutton. Routh. Beverley. 



854. Navicula humilis Donk. 



[Syn. Navicula inflata W. Sm., non Kiitz.]. 



S.W. — Hatfield district; Rossington (M. H. Stiles). Allerton. 

 CuUingworth. Roche Abbey (J. N. Coombe). 



Mid '^. — Hawksworth Springs. Holden Gill, near Keighley. 

 Boston Spa. Kiilinghall (G. Norman). Kildwick. 



N.W.— Mickle Fell. 



N.E.— Saltburn. Carlton Bank. 



S.E. — Waghen. Tick ton. Beverley. Wawne ; Market 

 Weighton Canal ; Beverley Parks ; Cottingham (G. Norman). 



855. Navicula nana Greg. 



[Syn. Pintiularia pygmma Ehrenb.]. 

 S.E. — River Hull; Cottingham; near Stoneferry (G. Norman). 



856. Navicula digitato-radiata Greg. 

 Var. Cyprinus (W. Sm.) V.H. 



[Syn. Navicula Cyprinus W. Sm.]. 

 S.E. — Dairycoats ; ditch near River Hull (G. Norman). 

 857. Navicula Reinhardtii Grun. 

 S.W.— Hatfield district (M. H. Stiles). 



Mid W. — In River Skell, Fountains Abbey (G. Stuart ; E. 

 Grove). Ribblehead. 



858. Navicula lanceolata Kiitz. 



S.W.— Cusworth District (M. H. Stiles). Bradford. CuUing- 

 worth. 



Mid W. — Kildwick. 



S.E. — Beverley Parks, near Woodmancy (G. Norman). 



859. Navicula Gastrum (Ehrenb.) Donk. 

 Mid W. — Cocket Moss, near Giggleswick. 



860. Navicula tumida W. Sm., 1853. 



[Syn. Navicula anglica Ralfs, 1861]. 



