32 
NORDSTEDT, DESMIRIACEiE SPETSBERGEXSES ETC. 
In insnl. Spetsb. ad Bel Sound (Nathorst) et Adventbay, 
Kobbebay (Berggren). 
15. C. undulatum Corda ß crenulatum Wittr. (Anteckn. 
p. 11; Euastrum (Cosmarium) crenulatum Näg. Gatt. einz. 
Alg. p. 120, t. 7 A, f. 7 c & d). 
Long. 0,00094" = 24 p. Lat. 0,0008" = 20 
In insula Beeren Eiland. 
16. C. pulcherrimum Nordst, (Desm. Brasil, p. 213 (175), 
t. III, f. 24). 
ß boreale n. var. (C. pulcherr. Lundell Desm. p. 34?). 
Tab. VI, f. 14. 
Differt a forma brasiliensi isthmo latiore, crenis 14(—16), 
in forma a 18(—20), tumore basali, non multum elevato, serie- 
bus granulorum 9 praedito, diametro transversali corporis maxima 
ad basin semicellularum (in a paullo supra basin) sita. 
Long. 0,0020—22" = 52—58 p. Lat, 0,00155" = 39 p. Crass. 
0,00095" = 24 p. Lat. isthmi 0,0009" = 23 p. 
In insul. Spetsb. ad Kobbebay, Adventbay (Berggren) et 
Bel Sound (Nathorst). 
17. C. Quasillus Lundell (Desm. p. 29, t. III, f. 10). 
Forma semicellulis, e vertice visis, in apice utroque granu- 
latis (granulis binis), in centro granulis nullis. 
Long. 0,0026—29" = 66—74 p. Lat. 0,0023—26" = 59— 
66 u. Crass. 0,000145—16" = 37—40 p. Lat. isthmi 0,00062— 
72" = 16—18 p. Lat. apic. 0,0009—115" = 22—29 p. 
In insula Beeren Eiland. 
18. C. abnorme ß triquetrum n. sp. Tab. VI, f. 15. 
C. submediocre, quarta parte longius quam latius, profunde 
constrictum sinu lineari angusto; semicellulae e basi subreniformi 
brevi pyramidales, dorso lato truncatse, angulis inferioribus subrec- 
tis lateribus paullum convexis, margine dense crenulatae, ad 
marginem versus granulis radiatim dispositis et tumore basali 
granulato ornatae; e vertice visa trigonae angulis truncato-rotun- 
datis, lateribus paullum concavis, medio tumore granulato in- 
