Acta Societatis pro Fauna et Flora Fennica,. 49, N:o 7. 29 



This species should be compared with C. promontorium 

 West, New Brit. Frw. alg. pi. 1 f. 14; C. luimile (Gay) 

 No rd St., West, Mngr. Ill pi. 85 f. 16—18; C. subdanicum 

 West, Mngr. Ill pi. 85 f. 25—26. 



Hab. Gov. of Archangel. PL 6 fig. 22—23. 



C. Blyttii W i 1 1 e var. pseudorichmondiae nov. var. 

 Forma cellularum eadem fere atque in var. richmondiae 

 Playf., Biol. Richm. Riv. pi. 3 f. 12 sed differt apice sub- 

 retuso non undulato et in area centrali verruca granulis 

 circumdata. A ventre visum oblongum medio utrimque 

 verruca seu papilla truncato-emarginata. Long. 20, lat. 16, 

 crass. 11, isthm. 4//. [N:o 1037]. 



This variety is in its general appearance very like the 

 var. richmondiae Playf., but is easily distinguished by the 

 central papilla surrounded by granules. Compare also var. 

 casinoense Playf., ibid. pi. 3 f. 13 and C. sabprotumidum 

 Nordst., West Mngr. Ill pi. 86 f. 19—25. 



Hab. (SW?), leg. Elfv. PL 6 fig. 16—17. 



C. sexnotatum Gutw.; West, Mngr. Ill pi. 86 f. 7. 

 var. denotatum, nova var. Semicellulae lateribus 4-undu- 

 latis, apice recto non undulato; membrana intra margines 

 radiatim granulata (sub ipso margine saepe granulis gemi- 

 natis) et in medio supra isthmum granulis 9 parvis et de- 

 pressis in series 3 longitudinales et 3 transversaies ornata. 

 A vertice visum oblongum medio utrimque leviter lateque 

 tumidum (granulis non conspicuis). Long. 28, lat. 22, crass. 

 14, isthm. 8//. [N:o 1175]. 



The outline of the cells very much resembles var. 

 tristriatum (Liitkem.) West, Mngr. Ill pi. 86 f. 8—9, but 

 the three cristae at the centre of the semicells, which are 

 characteristic of this species, are in our variety each re- 

 presented by 3 granules. Hereby it approaches C. sub- 

 crenatum Hantzsch. (West, Mngr. Ill pi. 86 f. 10—14). 



Hab. In a basin in the Botan. Garden, Helsingfors (S). — 

 PI. 6 fig. 24—25. 



C. abscissum nova sp. Cellulae mediocres, medio sinu 

 anguste lineari extrorsum extremo subito ampliato profunde 



