FRESH-WATER DIATOMS FROM ICKLAND 57 



Var. naviculacea Grun. De Ton. Syll. 652. V. H. Syn., Tab. 

 XLI, fig. 8. 



Grimsey (N.) O. D. 

 Area: Eur. 



Synedra radians (Ktz.) Grun. V. H. Trt. 312, Tab. X, fig. 423. 

 7 samples (S. 3, S.W. 4, E. 1). 

 Area: Eur., As., Grl. 



Synedra rostrata Pant. Pant. Bal. S. 76, Tab. VIII, fig. 4. 

 12 samples (S. 2, S.W. 4, N. 7). Hot spring: 1. 

 Area: Eur. 



Hustedt claims in Sud. p. 46, that Syn. rostrata is to be considered 

 a sporangial form "a us dem Gebiet der Synedra Ulna". 



Synedra rumpens Ktz. var.? fragilaroides Grun. cnt'r. De Ton. 680. 

 V. Syn., Tab. XL, fig. 12. 



38 samples (S. 14, S.W. 14, N.W. 1, N. 4, E. 4, s. 1. 1). Hot springs: 3. 

 Area: Eur., Am. 



Var. islandica var. nov., Tab. nost. V, fig. 76. 

 Long: 36 /<, lat: 3,2 , sir. 20 in 10 /<. 



Valva linear!, apices versus leniter attenuata. Striis media in 

 parte valvae aream nudam relinquentibus. 



Hallormstadr (E.) B. P. 



I have placed this small Synedra as a variant of S. rumpens, pos- 

 sibly to be placed nearest to S. rump, genuina (V. H. Syn., Tab. XL, fig. 

 14), owing to its close slriation; for the same reason perhaps related 

 to S. (Vaucherise var.?) capitellata Grun. (V. H. Syn., Tab. XL, fig. 26). 



*Synedra Ulna (Nitzsch) Ehr. V. H. Trt. 310, Tab. X, fig. 409". 

 207 samples (S. 50, S.W. 50, N.W. 6, N. 32, E. 69). Hot springs: 11 

 Area: Eur., Af., As., Am., Grl. 



Var. amphirlujnchns Ehr. V. H. Trt. 311, Tab. X, fig. 414. 



Minni Laxa (S.) A. F. 

 Area: Eur. 



Var. Danica Ktz. V. H. Trt. 1. c., Tab. c., fig. 415. 



148 samples (S. 33, S.W. 30, N. 18, E. 67). Hot springs: 7. 



Area : Eur., Af., Grl., B. E. 



In 60 samples (S. 12, S.W. 16, N.W.I, N. 2, E. 25, s. 1. 4) and in 2 

 hot springs I have noted S. Ulna, which however could not be deter- 

 mined accurately, they being only present as fragments or lying on the 

 connecting zone. 



Var. longissima W. Sm. V. H. Trt. 310, Tab. c., fig. 412. 

 Laugaa (S.) A. F., Krokur (S.) H. Js., Hornarfjordr i E.) St. 

 Area: Eur., Af. 



