Acta Societatis pro Fauna et Flora Fennica, 49, N:o 7. 31 



C. cymatopleurum N d t. var. tyrolicum Ndt, West, 

 Mngr. Ill pi. 65 f. 11 — 12. Forma cellulis maioribus pro- 

 fundius constrictis, apice non retuso; a vertice visum crassius 

 subangulosum. Long. 118, lat. 85, crass. 53, isthm. 28 //. 

 [N:o 1156]. 



Hab. Ekenas, Jusaro (S). PI. 6 fig. 28-29. 



C. perincisum, nov. nom. (Synon. = C. margaritiferum 

 Menegh. var. incisum Kirchn., Alg. Schles. p. 150 et in 

 litt. apud Nordstedt c. icon.; Borge, Torne Trask p. 13; 

 C. margaritif. forma Borge, Chi. Archang. p. 20 pi. 2 

 f. 15 sec. auct. ips. 1. supra, page 13). Cellulae magnae 

 medio incisura late aperto extrorsum paulum dilatata pro- 

 funde constrictae. Semicellulae subellipticae basi fere recta 

 apice late convexo; a vertice visae extense ovales lateribus 

 medio subrectis vix convexis. Membrana granulis rotundatis 

 depressis in ordines transversales, obliquos, concentricos 

 dense obsessa. Massa chlorophyllacea — ? Long. 63, lat. 57, 

 isthm. 19, crass. 32//. [N:o 831]. 



Our specimens were considerably larger than Borge's, 

 thus agreing with the measurements given by Boldt, but 

 the granules are smaller and more densely arranged than 

 stated by both these. In spite of these small differences 

 I think they belong to one species which, as already sug- 

 gested by Borge, is best regarded as a separate species. 

 The only species that I find resembling C. perincisum are 

 C. holmii Wille (Alg. Nov.-Zeml. og Kara-H. pi. 3 f. 2) 

 and C. pseudoholmii Borge (Torne Trask pi. 2 f. 1) but in 

 the vertical view these are strongly tumid. 



Hab. Gov. of Archangel. — PI. 6 fig. 26—27. 



C. magnificum Nordst., N.-Zeal. pi. 6 f. 19 page 62. 

 Forma ad var. suecicum Borge accedens. Pars glabra 

 membranae multo angustior; utrimque ad isthmum series 

 simplex punctorum (=pororum); a vertice visum non tu- 

 midum. Massa chlorophyllacea parietalis, in utraque semi- 

 cellula e laminis 4 parietalibus, quarum utraque nucleis 

 amylaceis 2 — 5 (saepe 3) plus minusve in series subaxiles 



