38 ARKIV FÖR BOTANIK. BAND 14. N:0 9. 



Distr. of the main form {brach, and mar.): Baltic (Gothl.), 

 Belgium, Atlantic coast of America, Behring Island. 



Mastogloia elliptica Ag. f. major nob. 



Valve 63 ]}. in length, 27 [i in breadth, thus considerably 

 larger than stated by Cleve, Syn. Nav. D. II, p. 152 (L. 

 22—45 |i, Br. 10—18 (i). 



Foss.: Kk. Knjäsha, rare {mar.). 



Distr. of the main form {brack, w.): Baltic, Caspian Sea, 

 Europe, America, Australia. 



Monoraphideae. 

 Rhoicosplienia Grun. 



Rhoicosphenia fossilis n. sp. — PI. 2, f. 48. 



Lower waive linear-clavate, with attenuated ends, 60 '^. 

 in length, 7 \>. in breadth. Upper end obtuse. Axial area 

 very narrow, central area narrow, lanceolate. Striae about 

 10 in 10 [i. (the distance is somewhat variable), strongly ra- 

 diate, except at the upper end, where they are transverse. 

 Upper valve unknown. 



Foss.: Kk. Knjäsha {mar.). 



Rhoicosphenia curvata Kütz. var. linearis n. var. 

 Valve linear, with acute ends, 10 times as long as broad, 

 c. 30 [J. in length. 



Foss.: Ab. Hindersmossen {brack, tv.). 



Cocconeis (Ehb.) Cl. 



Cocconeis Scutellum Ehb. var. parva Grun. — V. H. 

 Syn. Tab. 29, f. 8, 9. 



Foss.: Kk. Knjäsha, not rare. 



Distr. {mar.): Baltic, East Cape, Adriatic. 



Small specimens, from 13 [x in length and 8 [t. in breadth, 

 with 11 rows of puncta in 10 [j. occur intermingled with the 

 var. genuina Cl. 



Cocconeis Scutellum Ehb. var. ornata Grun. — V. H. 



Syn. Tab. 29, f. 6, 7. 

 Foss.: Kk. Knjäsha. 

 Distr. {mar.) : East Arctic and North Pacific Ocean, Austr. 



