W. WliSr AND G. S. WEST : ALGA-FI.ORA OF YORKSHIRE, 2tg 



Fa m I LY COSCINODISCIDE^. 

 Genus COSCINODISCUS Ehienb., 1838. 



1041. Coscinodiscus lacustris Grun. 



[Syn. Cydotella punctaia ^V. Sm.]. 

 S.E. — iVIarket Weighton Canal, near the River Foulney, 

 attached to Myriophylluin and Potamogeton (G. Norman ; 

 Griuiow). 



1042. Coscinodiscus radiatus Ehrenb. 



S.E. — ivIarket Weighton Canal ; Reservoir Waterworks, Hull 

 (G. Norman). Usually marine. 



