KONGL. SV. VKT. AKADEMIENS IIANDLINGAH. BAND 26. N:*) 2. 107 



fig. 7 in A. S. shews two longitudinal linos crossing the stria'- on each side of the median line, 

 which suggests some affinity to Caloneis, if this character is not due to an optical illnsicni. 



(). N. lucida Pant. (189o). — V. narrow, lanceolate, subacute. L. (1,2; B. 0,022 mm. Axial 

 area very narrow, not dilated in the middle. Transverse striic 12 in (t,(ii mm. almost parallel 

 throughout. — Pant. Ill PI. XVllI f. 264. 



Habitat? sBodas> fossil (Pant.). 



Under the name ^Y. incidtu Pantocsek figures (111 PI. XLV f. 216) a similar, but smaller and 

 more finely striate form, with subrostrate ends. 



7. N. parallelistriata Pant. (1889). — V. linear, attenuated towards the broad, obtuse ends. 

 L. 0,06'j; B. 0,017 mm. Central pores approximate, terminal in contrary directions. Axial area 

 linear, narrow. Stri<€ 17,5 in 0,oi mm. parallel. — Pant. II p. 52 PI. II f. 2(i. 



Brackish water: Hungary, fossil (Pant.). 



8. N. heteroflexa Pant. (1889). — V. linear-lanceolate, with broad, rounded ends. L. 0,074 

 to 0,11; B. 0,011 to 0,0 13 mm. Median poi'es approximate; terminal in contrary directions. Axial 

 area very narrow, linear. Strite 22 (28 accord, to Pant.) in 0,oi mm. (the median shorter than 

 the others) radiate in the middle, parallel towards the ends. — Pant. II p. 47 PI. II f. 34. 



Brackish water: Hungary, fossil! 



Var. constricta Pant. (1889). — V. slightly constricted in the middle, with cuneate ends. 

 L. 0,05 to 0,06; B. 0,011 to 0,012 mm. Striai 25 to 30 in 0,oi mm. — Pant. PI. II f. 27, 33. 



Brackish water: Hungary, fossil (Pant.). 



Var. minor Pant. (1889). — V. linear-lanceolate. L. 0,048; B. 0,oo95 mm. Striic 22 to 25 

 in 0,01 mm. — Pant. II PI. IX f. 162. 



Brackish water: Hungary, fossil (Pant.). 



This species is one of the most remarkable Navicuhe. Although in some respects divergent 

 from the rest of this group, especially by its radiate median strite, I have placed it here, as it 

 seems to be more akin to N. parallelistriata than to any other speeies. 



9. N, crassirostris Grun. (1880). — V. linear, with prolonged, rostrate and obtuse ends. 

 L. 0,048; B. 0,007.3 mm. Median line with approximate central pores. Areas indistinct. Striae 

 transverse, 27 in 0,oi mm. — Grun. A. D. p. 45 PI. Ill f. 57. 



Brackish water: Kara (Grun.). 



Var. Maasoensis Grun. (1880). — More elongated and with narrower ends. Strife about 25 

 in 0,01 mm. — Grun. A. D. p. 46. 

 Marine: Finmark (Grun.). 



10. N. Lineola Grun. — (1884). — V. linear with rounded ends. L. 0,oi6 to 0,o5i; 

 B. 0,0025 to 0,003 mm. Central pores approximate. Strise extremely fine(?) — Grun. Franz Jos. 

 Land D. p. 104 (52) PI. I f. 45, 46. 



Marine: Franz Josephs Land (Grun.). 



Var. perlepida Grun. (1884). — V. with somewhat constricted ends. L. 0,o2 to 0,034; 

 B. 0,002 to 0,0033 ram. — N. jicrlejnda Grun. Franz Jos. Land, D. p. 104 (52) PI. I f. 44. 

 Marine: Franz Josephs Land (Grun.). 



Naviculse Orthosticlise Cl. 



Valve usually elongated, lanceolate to linear. Median line wath small or elongated central 

 nodule, sometimes transversely dilated into a stauros, and with small or indistinct terminal fissures. 



