W. WEST AND G. S. WEST: ALGA-FLORA OF YORKSHIRE. 211 



995. Nitzschia Tryblionella Hantzsch. 



[Syn. Tryblioiiella gracilis ^V. Sm.]. 



S.W.— Goole (J. Harrison). Roche Abbey (M. H. Stiles ; 

 J. N. Coombe). Doncaster town water ; Firsby reservoirs ; 

 Rossington (M. H. Stiles). 



N.E.— Saltburn. 



S.E. — Market YVeighton. Stoneferry; Hornsea Peat Deposit 

 (G. Norman). 



996. Nitzschia angustata (W. Sm.) Grun. 



[Syn. Tryblioneila angustata \<! . Sm.]. 

 S.W.— Roche Abbey (M. H. Stiles ; J. N. Coombe). 

 S.E. — Newsholme. Beverley!; Market VVeighton Canal; 

 Anlaby (G. Norman). 



997. Nitzschia constricta (Kiitz.) Pritch. 



[Syn. N. dubia W. Sm.]. 

 S.W. —Goole (J. Harrison). 



Mid W. — Boston Spa. Hawksworth Springs. Bolton Woods. 

 Ribblehead. 



S.E. — Beverley. Loftsome Bridge, near Wressle. Tickton. 



Routh. Near Meaux .-^bbey. Waghen. Market \Veighton. 



Cottingham; near Stoneferry; Wawne; Haltenprice; Dairycoats; 



Anlaby to Hessle Road; Skirlaugh; Stepney Lane (G. Norman). 



Forma minor Rabenh. 



Mid W.— Baildon. 



S.E. — Market Weighton. 



998. Nitzschia plana W. Sm. 



S.E. — Brackish ditch, near River Hull (G. Norman). 



999. Nitzschia parvula W. Sm. 



Often found on damp ground and amongst damp moss. 

 S.W. — -Doncaster. Roche Abbey (J. N. Coombe). Ogden 

 Clough. 



Mid W. — Boston Spa. Bolton Woods. Holden Gill, near 

 Keighley. 



N.W.— Great Shunnor Fell. 



N,E. — Strensall. Marske. Rievaulx Abbey. 



