378 JOHS. Bfni. PKTKHSK.N 



Ceraloneis Khrh. 



Ceratoneis Arcus Kiil/ V. Ilciiifk, Traiti-, p. iiUt). IM. 10. li j^. 101. 



K. ki-1. 2.") S. k-c'l. L. ;i8(). 



Accordin« lo tlic lilcralurc tliis species should occur cspccially in 

 runninii watcr. and nolably in niountain streanis. The two habitats I 

 •jive from Iceland are likcwise |)lac'es whcre there is riiniiiiij^ water. al 

 any rate at cerlain limes of Ihe year. The species Ix'iiijf iuiind by 

 Oslrup in 120 samples from Iceland, \ve must concludc thai il is no 

 aerial alga, but thai it may still survive some time afler Ihe strcani in 

 which it ociurred iias dricd up. 



V. Achnantheæ. 



Cocconeis (Ehrb.) Cl. 



Cocconeis placentula Klirb. C\. Svnops. IF. p. 169. V. Heurck Syn. 

 PI. X\.\. lig. 2(1. 27. 



N. kel. 109. 



The species occurs habitually in trcsh water. also in Iceland Ostrup 

 126 samples). Hustedt, however, lound it in a niountain cave. It is 

 hardly an aerial species. 



Microneis Cl. 



Achnanthes delicatula Kutz. Cl. Svn. II !>. 190. V. H. .Svn. PI. 27, 

 fig.3. 4. 



N. kel. 252 — Vestmannacyjar L. 399. 

 Area: Eur., Afr., As., Greenl. 



Brackisli water species. Found on Vcslmannaey in a niountain cave 

 at a hci{»lit of 20 m tojjether witli true fresh water species and ollier 

 brackisli water s])ecies, likewisc in Ilusavik, amonjj Pntsiohi rrispa and 

 fresh water and terrestrial forms. It is hardly any true aerial aljja. but 

 may be cxpecled to occur amoiig such in coastal regions. 



Achnanthes linearis ^V. .Sm. Cl. Syn II. p 18S. V. Heurck. Syn. 

 PI. 27. lig. :ji, :J2. 



N. Icel. 14 0. 



I'ound in a ditcli by the roadside among desiccaled algæ. '»Forma- 

 lion passagere ;. 



Achnanthes microcephala Kutz.) (".run Cl. Syn. II. p. 188. V. II. 

 •Syn. PI. 27. lig. 20-23. 



H. Icel. L. 25 - S. Icel. L. 386. 

 Area: Eur. 



The s|)ecies was found by Ilustedl on irrigatcd mosses in Silesia, 

 and about ils occurrence in (lermanv v. Schonfeldl slales thai il is 



