Acta Societatis pro Fauna et Flora Fennica, 49, N:o 7. 37 



medio autem undula maxime prominenti; apice lato levis- 

 sime retuso. In centro cemicellularum scrobiculae singulae. 

 A vertice visum ellipticum. Long. 34 — 35, lat. 21—22, crass. 

 13, isthm. 7 fi. [N:o 861]. 



This variety is easily distinguished by its broad apex 

 (only very little narrower than the base of the semicell) 

 and the strongly prominent median undulation. Compare also 

 various forms of C. trilobulatum. 



Hab. Esbo (S), leg. C. Cz. — PI. 7 fig. 13—14. 



var. excavatum (Eichl. & Gutw.) West, forma 

 duplo-maior. Forma cellularum eadem atque in typo. Long. 

 41,4, lat. 27,6, crass. 16,5, isthm. 4,6//. [N:o 833]. — Compare 

 also C. venustum Breb.; West, Mngr. Ill pi. 66 f. 2. 



Hab. Gov. of Archangel. PI. 7 fig. 17—18. 



C tinctum Ralfs. var. tumidum Borge, Regnell, exp. 

 pi. 3 f. 25. Forma sinu introrsum acuto, cellulis a vertice 

 visis minus tumidis; membrana saepe luteola. Long. ll,i, 

 lat. 10,6, isthm. 6,6//. [N:o 1035]. 



Hab. (SW?), leg. Elfv. PI. 7 fig. 15-16. 



C. bacillare Liitkem., Desm. Bohm. pag. 484. (Sy- 

 non. = Penium inconspicuum West, New Brit. Frw. alg. p. 

 4 pi. 1 f. 6—7 and Mngr. I pi. 10 f. 15—17). Long. 19, 

 lat. = crass. 7,2, isthm. 6,6, apex circ. 4 ,«■. [N:o 1028]. — 

 Somewhat broader than the English form. Chloroplasts with 

 one pyrenoid in each semicell. 



Hab. Raikala near Imatra Falls (SE), leg. Hj. Hjelt. — 

 PI. 7 fig 38. 



C. perminutum West, Frw. alg. Columbia page 1041. 

 (Synon. = Cylindrocystis minutissima Turn.; West, Mngr. I 

 pi. 5 f. 9; synon. = Cosmarium pseudarctoid.es Strom, Frw. 

 alg. Telemark page 31 pi. 3 f. 7—8). — Long. 10,6—11,9—12,6 

 lat. = crass. 6,6, isthm. 5,3//. [N:o 1178]. 



In his paper (1. c.) 1920 Strom created a new name 

 for this species, which cannot be accepted because West 

 (1. c.) already in 1914 transferred it to Cosmarium giving it 

 a new name. — The cell-wall is thin with a few scattered 

 pores (fuchsin + potass, acet.!) The chloroplasts are very 



