370 ERNST 0STRUP 



Synedra affinis var. rupicola Grun. V. H. Syn., 1. c., fig. 27. 

 Area: Eur., Grl. 



Synedra affinis var. tabnlata Ktz. V. H. Syn., 1. c., fig. 9 A. 

 Area: Eur., Aust., Grl. 



Synedra affinis var. typica Ktz. A. S. Atl., Tab. CCCV,,figs. 6 12, 



Area : Ubiquist, Grl., A. S. 



Amongst these, the most frequently occurring species are: 



typica: 106 samples (S. 17, S.W. 48, N.\V. 20, X. 11, E. 10). 

 tabnlata: 44 samples (S. 4, S.\V. 20, X.W. 6, X. 13, E.I). 

 gracilis: 41 samples (S. 2, S.W. 12, X.W. 7, X. 17, E. 3). 

 parva: 14 samples (S. 2, S.W. 5, X.W. 3, X. 2, E. 2). 



Synedra crystallina (Lyngb.) Ktz. V. H. Trt., 315, Tab. X, fig. 435. 



Vestmannaeyjar (S.), H. Js. 

 Area: Eur., Afr., As., A. S. 



Synedra curvata sp. nov. Tab. nost., fig. 14. 



Long.: 104178/7, lat. : media in valva, 3,6 5 ,, str. 19 20 

 in 10/f. 



Valva linear!, apices versus leniter attenuata, curvata. Striis 

 marginalibus. 



Isafjorflur (N.W.), C. H. O. 



Owing to its marginally situated striae, this species is probably most 

 closely allied to the form-series of Synedra affinis. It has no connection 

 with Syn. curvula Ktz. Bacil. , 65, tab. XV, fig. II <a fresh-water species 

 from Xordhausen in Saxony). 



Synedra Gailloni Ehr. V. H. Trt., 312, Tab. X, fig. 424. 



16 samples (S. 1, S.W. 15). 

 Area. Eur., Afr., As., Am. 



In a sample from Melvik, near Reykjanes (SAY.), C. H. O., I have 

 found a Synedra, which corresponds well with Syn. capensis Grun. V. H. 

 Syn., tab. XLII, fig. I, a form closely allied to Syn. Gail. 



Synedra Hennedyana Greg. V. H. Trt., 317, Tab. X, fig. 438. 



Vattarnes (E.), H. Js. 

 Area: Eur. 



Synedra investiens W. Sm. V. H. Trt. ? 313, Tab. X, fig. 425. 



62 samples (S. 17, S.W. 25. X.W. 5, X. 8, E. 7). 

 Area: Eur., Grl. 



Synedra kamtschatica Grun. Cl. & Gr. A. D., 10(5; 0st. 0stg. mar.,. 

 Tab. VII, lig. 85. 



8 samples (S.W.I, X.W.I, X. 4, E. 2). 

 Area : Grl., A. S. 



