J 36 KAARE MÜNSTER STRØM. 



lateral margins convex; apex rounded. Sinus very narrow; 



isthmus about Vs» or ^^ss, as broad as the cell. Vertical 



view elliptic. Cell-wall smooth. Ghloroplast axile with one 



pyrenoid. 



Dimensions of cells: 



long. 20 — 22 (.i\ lat. 16 — 17,5 (.i; lat. isthm. 5—6/^; crass. 9.«. 



Wladikaokas — Kasbek. 



40 Cosmarium pseudonitidulum Nordst. 



The determination is not quite sure as the species was 



dried. 



Askabad. 



41. Cosmarium nitidulum De Not. 



long 32,5 /<; lat. isthm. S f.i; lat. 22;tt; crass. 14«. 

 Kasbek — Mleti. 



42. Cosmarium impressulum Elfv. 



Wladikaokas — Kasbek. long. 18,5 /^; lat. 15;f<; lat. isthm. 4,5 ^tt. 

 A little smaller than the typical form. 

 ^^'di.wdiV. punctatum nov. var. Pl. II Fig. 11. 



Cells very small, a little (1^) longer than broad. Sinus 



narrowly linear. Semicells semi-elliptic with eight slight 



undulations. 



Vertical view elliptic. Cell-wall delicately punctate. 



Chloroplast axile with one pyrenoid. 



Dimensions of cells: 



long. 15/<; lat. 12 /t; lat. isthm. 4 ^tf. 



The variety differs from the typical form in being punctate, 



it is also considerable smaller, and with less marked 



undulations. 



Askabad. 



43. Cosmarium lœve Rabh. 



Wladikaokas — Kasbek; Askabad; long. ^1 /.i; lat. 13,5 u. 

 lat. isthm. 5 f.i; Tiflis. long. 21 u; lat. 14 ^u; lat. isthm. 5 /^i. 

 General and abundant. 



