50 ARKIV FÖR BOTANIK. BAND 11. N:0 9. 



whole marginal part of the valve, continued each by two 

 or three close costal lines to the narrow lanceolate-fusiform 

 central area. 



Foss.: Sat. Panelia, rare {Litorina-deposit) . 



There is a resemblance between this delicate Surirella, 

 belonging to the tribe of the fastuosae, and a more rounded 

 obtuse form, recently described in Contrib. Diat. Venezia 

 1913 by Mr A. Forti and named Surirella striatida Turp. 

 var. Azpeiticae, from a deposit in Modena, Tab. 19, f. 2. 

 Some allied forms are figured in A. S. Atl. Tab. 5, f. 12 as 

 Surirella fastuosa var., Atl. Tab. 24, f. 28 as Surirella recedens 

 A. S. and especially in the Atl. Tab. 299, f. 32 as S. septen- 

 trionalis Hust. 



Surirella nana n. sp. — PI. 4, f. 93. 



Valve very small, linear with rounded-obtuse ends, 4 times 

 as long as they are broad. Length 15 [j-, breadth 4 a. Costae 

 marginal, delicate, 11 — 12 in 10 u.. Centrum of the valve 

 smooth. 



Foss.: Ab. Hindersmossen, rare. 



The nearest relations of this minute Surirella seem to be 

 two small forms figured by Pantocsek in D. Balat. See, Tab. 

 11, f. 283, as Sur. angusta and in ff. 284, 286 SlS Sur. minuta 

 (the determination is not exact, according to O. Müller, Bac. 

 Süd-Patag., p. 38). But the present form is still smaller, 

 more delicate and more closely costate. 



Surirella spiralis Kltz. — V. H. Syn. Tab. 74, f. 4, 7. 



Syn. Surirella jlexuosa Ehb., Pant. D. Balat. See, Tab. 

 14, f. 305. 



Ladoga. Foss.: Sat. Panelia; Ka. Viborg-dep.(CLEVEl894). 



Distr. {fresh iv.): Eur., Asia. Fossil in deposits from the 

 Ancylus-Sea. 



Campylodiscus Ehb. 



Campylodiscus angularis Greg. — D. of Clyde, Tab. 3, 

 f. 53. 



Foss.: Kk. Knjäsha, Koudajärvenpää, frequent. 



Distr. (mar.): West and East Arctic Sea (common accord- 

 ing to Cleve); Scotland. 



I 



