KOXGL. SV. VET. AKADEMIENS HANDLIN6AR. BAND 26. N:0 2. 175 



Cymiella helvetica is a very common species, easily recognized by its straight terminal 

 fissures. Under tlie name Encyonema Gerstenbergeri Grdnow has described (Banka D. p. 9 PI. I 

 f. 11 ; 1865) a form, remarkable for the terminations of the median line, which are unusually distant 

 from the ends of the valve. I have seen from various localities several specimens closely agreeing 

 with the figure published by Grunow, and I have convinced myself that these are abnormal forms 

 of C. helvetica. 



* C. hCTesensis Pant. (1889). — V. boat-shaped, with obtuse ends. L. 0,o62; B. 0,oi3 mm. 

 Median line bent; its central pores very distant. Axial area narrow, slightly dilated around the 

 central nodule. Striae 11,5 to 13,5 in 0,oi mm. slightly radiate, punctate. — Pant. II p. 40 

 PI. Ill f. 53. 



Brackish water: Hungary, fossil (Pant.). 



This species is unknown to me. The fig. and description given by Pantocsek are insufficient 

 for deciding as to its relations to other boat-shaped Cymbellai. 



* C. Chyzerii Pant. (1889). — V. hoat-shaped, with the ventral margin slightly gibbous in 

 the middle. Ends subrostrate, obtuse. L. 0,0825; B. 0,oi45 mm. Median line arcuate, its central 

 pores approximate. Axial area narrow, not dilated in the middle. Strige 10 to 12,5 in 0,oi mm. 

 Ventral strise crossed by »a black line»(?) — Pant. II p. 40 PI. XI f. 194. 



Brackish water: Hungary, fossil (Pant.). 



This species is unknown to me. The description and the figure given by Pantocsek are 

 insufficient for ascertaining its relations to other boat-shaped Cymbellae. It may come near to 

 C helvetica, C. lanceolata, C. cymbiformis. 



59. C. aspera Ehb. (1840). — V. boat-shaped, with strongly arcuate dorsal margin and 

 straight, centrally gibbous ventral margin. Ends obtuse, rounded. L. 0,i5 to 0,i8; B. 0,033 mm. 

 Median line arcuate. Axial area linear, slightly dilated in the middle. Strise 7 to 9 in 0,oi mm. 

 slightly radiate, punctate; puncta 12 to 15 in 0,oi mm. No row of isolated puncta on the ventral 

 side. — Coccon. asperum Ehb. Ber. 1840 M. Gr. V: i f. 1 etc. Petit Journ. de Microgr. 1878 Mars et 

 Avril f. 3. HjSeib. D. d'Auvergne PI. Ill f. 10. Cy. lanceol. var. aspera Brun D. des Alpes p. 57 

 PI. IX f. 16? Cy. gastroides KtJTZ. Bac. p. 79 PL VI f. 4 6 (1844). A. S. Atl. IX f. 1, 2; X f. 7. 

 V. H. Syn. p. 63 PI. II f. 8. Grun. Franz Josephs Land D. p. 97 (45) PL I f. 7. G. gigantea Pant. 

 Ill PL XXI f. 321 (1893)? 



Fresh water: Franz Josephs Land (Grun.), Iceland! Norway (Dovre, Laurgaard)! Sweden 

 (Lapland to Skane)! Finland! France! Britain! Belgium! Germany! Switzerland! Savoy! Italy! 

 Japan! New Zealand! 



Var. minor V. H. (1880). — Smaller, with strongly arcuate median line. L. 0,0 7 to 0,o8 

 mm. — Cy. gastr. forma minor V. H. Syn. p. 63 PL II f. 9. 



Var. neogena Grun. (1882). — L. 0,175; B. 0,033 mm. Striae about 8 in 0,oi mm., 12 inO,oi 

 mm. towards the ends, punctate; puncta about 14 in 0,oi mm. — Cy. gastroides var. neogena Grun. 

 Foss. D. Oster. Ung. p. 141. 



Fresh water: Hungary, fossil (Grun.). 



Var. dubravicensis Grdn. (1882). — L. 0,168; B. 0,027 mm. Terminal nodules very strong, 

 at some distance from the ends, surrounded by short striae. Striae 6 to 9 in 0,oi mm.; their 

 puncta 14 to 17 in 0,oi mm. — Cy. gastr. var. dubr. Grun. Foss. D. Oster. Ung. p. 141 PL XXIX 

 f. 30. Pant. IU PL XVH f. 251. 



Fresh water: Hungary, fossil (Grun.). 



Var.? crassa Grun. (1882). — V. short and broad vdth rounded obtuse ends. L. 0,073; 

 B. 0,024 mm. Median line strongly arcuate. Axial area narrow. Striai 6 or 7 (middle) to 9 

 (ends) in 0,oi mm. punctate; puncta 16 to 17 in 0,oi mm. The strise are on the ventral side 

 crossed by a short depression. — Grun. Foss. D. Oster. Ung. PL XXIX f. 28. 



Fresh water: Hungary, fossil (Grun.). 



