58 ARKIV FÖR BOTANIK. BAND l-t. N:0 9. 



Grammatophora arcuata Ehb. — östrup, Mar. D. 0st- 

 Gronl. Tab. 6, f. 74. —Icon. nost. PI. 3, f. 65 (short frustule). 



Foss. : Kk. Knjäsha, Koudajärvenpää, frequent; Ok. Pal- 

 tamo, rr. 



Distr. [mar.): Arctis and Antarctis. 



Mr 0STRUP thinks this species is a mere variety of 

 Grammatophora islaiidica Grun., which seems plausible enough. 

 The folded diaphragms are exactly similar to those of Gramm, 

 serpentina, only the striation is a little coarser, 13,5 punctate 

 striae in 10 [j- instead of 18 by the latter. Greenlandian 

 specimens of Gramm, arcuata have only 10 striae in 10 [Jl^ 

 according to Mr östrup. Considering this variability in the 

 number of striae, this form might perhaps as well be regarded 

 as a variety of Gramm, serpentina. The length of Finlandian 

 examples varies between 30 and 60 a, and the number of 

 folds with the length. 



Grammatophora marina (Lyngb.) Kütz. var. macilenta 

 W. Sm. — V. H. Syn. Tab. 53, f. 16. 



Foss.: Kk. Knäsha, Kuodajärvenpää, frequent; Ok. Pal- 

 tamo, rr. 



Distr. {mar.) Arctic Sea, Europe, Asia, Africa. 



Grammatophora hyalina n. sp. — Syn. Grammatophora 

 oceanica Ehb. var. macilenta suhtilis? 0str. Mar. D. 0st- 

 Gronl., p. 340, Tab. 2, f. 11. 12, 19. 



Valve linear, with rounded, slightly gibbous ends, 50 — 

 93 [J. in length, 4 — 5 a in breadth. Diaphragms not folded. 

 No striation visible. 



Foss.: Kk. Knjäsha, frequent; Koudajärvenpää. 



Distr. {mar.): West Greenland. 



No doubt this perfectly smooth form is identical with 

 the Greenlandian Grammatophora, that östrüp refers to Gr. 

 oceanica Ehb. var. macilenta suhtilis Grun. with hesitation, 

 because no striation is visible. I have not succeeded any 

 more than Mr Ostrup in finding the slightest trace of a 

 striation, though I have observed number of frustules. 



Grammatophora Sagitta n. sp. — PI. 4, f. 97. 

 Valve linear, with slightly protracted, acuminate ends. 

 Length 60 jj., breadth 7 a. Frust«le unknown. 

 Foss.: Kk. Knjäsha, rare. 



