363 



Farn. Oscülatoriaceae. 

 Gen. Phormidium Kütz. 



Richter angiver Ph. laininosuin Gom. (under Navn af Hypeothrix 

 gloiophila [Kütz.] Rab.) fra Karajak Nimatak. 



Phormidium-Arter findes i Prøver fra Unortok samlede af 

 Jessen, men IMaterialet var desværre opbevaret i Spiritus, saa en 

 Bestemmelse vil næppe give sikkert Resultat. Den tidligere omtalte 

 Phormidium- Art fra en „Sandslette foran Indlandsisen" var endnu 

 daarligere bevaret, den havde Traade der var 1 ,3 — 1 ,9 ц tykke. 

 Skillevægge var utydelige, Skeder tynde og farveløse. 



Gen. Oscillatoria Vauch. 



1) 0. amoena Gom. — Gomont Tome 16 pag. 225 PI. VII 

 fig. 9. La. Fil. 5 //. — Igaliko. (Vahl.) 



2) 0. breris Kütz. — Gomont Tome 16 pag. 229 Tab. VII 

 fig. 14. La. Fil. 4 ^6!!. — Fiskernæs. 



3) 0. cblorina Kütz. — Angives af Richter fra Umanak. 



Fam. Rivulariaceae. 

 Gen. Calothrix Ag. 



C. parietina Thuret. — Bornet et Flahault Tome 3 pag. 366. 

 La. Fil. 10 — 13 fj.. — Kingua Neriak, Kingua Sermiliarsuk. 

 Den angives af Richter fra Karajak. 



Gen. Rivularia (Roth.) Ag. 

 R. borealis Richter. — Angives af Richter fra Ikerasak. 



cells, the mucuos being less thick around the spores ; the mucuos sheath 

 is often consti'icted in such places лтЬеге the vegetative cells come into 

 contact with each other. The mucuos is colourless. The vegetative 

 cells are globose and 9,7 /л in diameter. The heterocysts are nearly 

 globose and 10,4 //. in diameter. The spores do not come into contact 

 with the heterocysts, they occur singly or arranged in a series of a few 

 together. The episporium is colourless and glabrous; length of spore 

 30 /л; breadth 10,4^.. At the spot where the spores come into contact 

 with the vegetative cells the episporium is often shaped like a small 

 cup, in which the vegetative cells occur. The colour of the filaments 

 is somewhat faded, I belewe it had been pale blue-green. The cells 

 contain numerous air-vacuoles. The thickness of the filaments, the 

 mucuos sheath included, is 32 /a. 



