304 .iDiis. Hovi; im;i i;hsi:.\ 



E. Icel. FIjotsdaliir, on ruck wilh running walcr '^^ c 1914. — 

 S. Ii'cl. "Laiigarvas"? leg. Stp.! ncar margin of nortlicrn spring, 

 lemp. =- 100" C. Hcvkir. Icnij). of spring. lOU 102*^ (.Stp.;! 



Arca: .Ml c-onlincnls, La|)i)lan(i, Fn-'roes, .Maska. 



In Museum Holanirum Ilauniense a specimcn exisls (coiiecled l)y 

 Steenslruj) on thc label ol" wliicli is wrilten: '"Meikum. Temp. of spring 

 100 ^'—102 *^'? Coriaceous slratified Oscillalorium-fell IVoin llie margin". 

 On the oulside of tlie capsule is writlen in Liebman's hånd: "Scijlonciud 

 ('.hili()n<)i)l<istes Liebm." with a shorl diagnosis which in tiie main agrees 

 wilh Ihat in Flora danica il. c.) and in Liebman 1811. \n cxaminalion 

 of the sample |)roved thai il aclually was a ScN'tonema the threads of 

 which were 9—22 // in diameter, measured on the same thread. When 

 young, the sheaths are thin, colourless, later lliey bec-ome brown, and 

 the layers are scarcely diverging. There can then be little doiibt tb:il(l) 

 we here have to do with the original specimcn of .S. CJitlwiiojjlastes 

 Liebm. and that (2) this species is identical with .S. mirahile i Dillw.) Bern. 



Tilis species has generally bcen found on moist rocks and on moss, 

 but rarely in water. Steenstrup found it in South Iceland on two lo- 

 calities at hot springs. That this species thrives well here is presu- 

 mably due to the faet that the earth around the hot springs is kept 

 regularly moist by the va|)our. For the rest, no statements exist as to 

 whcther it thrives jjarticularly well at higher temperatures. 



Scytonema myochrous (Dillw.^ Ag. 

 Bornet et Flahault, Revision III p. 104. 

 S. yrcicile Habenhorst Algen, nr. 977. 



E. Icel. Fljotsdalur. Rocky walls over which water was tiickling 

 ^°/6 1914 (4 samples). 



Area: All continents, .Spitsbergen, Greenland, Alaska. 



The species is often found on localities corresponding to the Ice- 

 landic ones; but it is also found in lakes foi'ming felted coatings over 

 the stones fHaumann 1911 p. 5(S), and detached pieces of such coatings 

 may sometimes form Æ7ay/o/."V<^'-lormations (Ljung(|vist 1915 p. li. V.. 

 Bachmann (1915 p. 51) refers lo the species as calcivorous when living 

 on limestone. On the other band, if it grows in water it seems to be 

 incrustcfh with lime (Le Roux 1907 p. 340\ 



In the l-"li(')tsdalur it occurred on several perpcndicular surfaces t)f 

 rocks forming a thick, almost black coating, often of great extent. In 

 some piaces an abundance of water streamed down over the growths, 

 others remained rather dry. During the summer they are und()id)ledly 

 often liable to suller from a considerable drought as the walls of the 

 rocks faced south-east. i. c. might be heated by the sun to a high degree. 



Scytonema crustaceum .\g. 



BoriH'l et Flaiiaiill, Revision p. lOfi. 



E. Icel. Fljotsdalur, black, thin coatings on the rocky wall ^"/e lill 1. 



Area: Eur., As., .\m.. Lappland. 



Togcther with (Uilolhiix /xuicliiKi . (iloeocapsa (ilf)iii(i , Schizolhrix 

 Heu/leri it formed thin. black coatings which but with difliculty were 



