FRESH-WATER DIATOMS FROM ICELAND 47 



Lagarfljöt (E.) B. P. 



I consider this form abnormal, and have therefore not classified it 

 as an independent species. 



Nitzschia (Hassall 1845, W. Smith) Grun. ch. em. 1880. V. H. Trt. 382. 

 Tryblionella (W. Sin. ex p.) Grun. V. H. Trt. 384. 



Nitzschia angustata (W. Sm.) Grun. V. H. Trt. 385, Tab. XV, fig. 498. 



II samples (S. 2, S.W. 4, X. 3, E. 2). Hot spring: 1. 

 Area: Eur., As., Am. 



In a sample from Geysir, Blesö (S.W.) Stp., I have found a Nitzschia 

 angustata, a delineation of which I have given on Tab. nost. V, lig. 71. Its 

 dimensions are: long: 72 n, lat: 54 //, str. 14 in 10 u punctatis. It has 

 more attenuated apices than the typical N. ang. 



Nitzschia debilis (Arnotl) Grun. V. H. Trt. 385, Tab. XV, lig. 498. 



Reykir (S.) Stp. 



Area: Eur., Grl., J. M., Spb.. Fz. J. 



Apiculatœ Grun. 1880. V. H. Trt. 387. 



Nitzschia apiculata (Greg.) Grun. V. H. Trt. 387, Tab. XV, lig 505. 

 18 samples (S. 2, S.W. 3, E. 12. s. 1. 1). 

 Area: Eur., As., Am.. Grl., B. E. 



Dubice Grun. 1880. V. H. Trt. 388. 



Nitzschia commutata Grun. V. H. Trt. 389, Tab. XV, fig. 512. 

 4 samples (S. 1, S.W.I. N. 2). Hot spring: 1. 

 Area: Eur., Af., As. 



Nitzschia Jonssoni sp. nov., Tab. nost. V, fig. 72. 

 Long: 48//, lat: 7 //, punct. carin. 6,5 in 10/*, str. subtilissimis. 

 Valva hantzschioidea, apicibus moderate productis. Punctis ca- 

 rinalibus prolongatis, medianis duobus spatiatis. 

 Seyöisfjord (E.) H. Js. 



Nitzschia Nathorsti Brun. Brun J.M. et E. Gi\ 9, Tab. II, fig. 5. 

 7 samples (S. 5. N. 2). Hot spring: 1. 

 Area: Grl., J. M.. Fz. J. 



Nitzschia serians Rabh. CI. & Gr.A. D. 78. V. II. Syn., Tab. LIX, 

 fig. 23. 



Thingvellir (S.W.) K. W. & Ho. 

 Area : Eur., As. 



Nitzschia stagnorum Rabh. CI. & Gr. A. D. 78. V. H. Syn., Tab. LIX, 



fig. 24. 



Berufjôrôr (E.) H. Js. 

 Area: Eur., Af. As. 



