44 p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



median strife of unequal length. — T. M. S. IV p. 40 PI. V f. 4, 4*. Ralfs in Pritch Inf. VII 

 f. 70. A. S. N. S. D. I f. 30. Atl. VI f. 7. Donk. B. D. p. 17 PI. Ill f. 2. Pant. Ill PI. XLI 

 f. 568. Pinnul divaricata O'Mbara M. J. VII p. 116 PI. V f . 7 (1867). 



Marine: Finmark! North Sea! Naples! Sebastopol! Ceylon! China! Japan! Hungary, foss.! 



Var. capitata Pant. (1889). — V. with capitate ends. L. 0,io9; B. 0,o4 8 mm. Striae 10,5 

 in 0,01 mm. — Pant. U p. 49; III PI. XXXH f. 461. 



Marine: Hungary, fossil (Pant.). 



Var. minor Pant. (1889). — V. elliptic-elongated, with capitate ends. L. 0,o7 5; B. 0,o3 

 mm. Striae 10,5 in 0,oi mm. — Pant. II p. 49. 



Marine: Hungary, fossil (Pant.). 



Var. elongata Pant. (1889). — V. elliptic-lanceolate. L. 0,i4; B. 0,06 mm. Striae 10 to 11 

 mm. Puncta 10 to 11 in 0,oi mm. — N. humerosa v. elongata Pant. II p. 48 PL X f. 175. 



Marine: Hungary, fossil: * 



21. N. Alpha Cl. (1893). — V. broadly lanceolate, with obtuse, subrostrate ends. L. 0,o62; 

 B. 0,03 mm. Median line with incrassate central pores, and the terminal figsures turned in contrary 

 directions. Striae 7 in 0,oi mm., a little closer at the ends (9 in 0,oi mm.), radiate, coarsely 

 punctate; puncta 8 in 0,oi mm. Median striae of unequal length. — Diatomiste II p. 13 PI. I f. 4. 



Marine: Japan! 



22. N. Jentzschii Grun. (1882). — V. elliptical, with rounded ends. L. 0,oi7 to 0,02; 

 B. 0,009 to 0,0115 mm. Axial and central areas indistinct. Striae 8 or 10 (middle) to 12 or 16 

 (ends) in 0,oi mm., frequently closer on one side of the valve, radiate throughout, punctate; puncta 

 22 in 0,01 mm. — Foss. D. Osterr. Ung. p. 156 PL XXX f. 64. 



Fresh or slightly brackish water: Domblitten, fossil (Grrun.), Finland, Abo! Sweden, Mala- 

 ren! Gulf of Bothnia! 



This species seems to connect the] Punctatce with N. lucidula and N. Atomus among the 



23. N. torneensis Cl. (1891). — V. lanceolate, with obtuse ends. L. 0,oi7 to 0,024; B. 0,oo8 

 to 0,01 mm. Axial area indistinct, central area small. Striae 14 in 0,oi mm., radiate at the ends, 

 coarsely punctate; puncta about 14 in 0,oi mm. — D. of Finl. p. 33 PL II f. 6. 



Slightly brackish water: Gulf of Bothnia (Tornea, Pitea)! 



Var. dhoensis Cl. (1881). — V. elliptical. L. 0,012; B. 0,oo8 mm. — 1. c. f. 7. 



Fresh water: Finland, Lake Lojo near Abo! 



24. N. lacustris Greg. (1856). — V. lanceolate, with subacute or subrostrate ends. L. 0,o35 

 to 0,055; B. 0,016 to 0,018 mm. Axial area narrow; central area small, but distinct, orbicular. 

 Terminal fissures seem to be turned in contrary directions. Striae 14 to 16, radiate at the ends, 

 distinctly punctate; puncta about 18 in 0,oi mm., larger near the areas. — M. J. IV PL I f. 23. 

 Cl. D. of Finl. p. 34 PL II f. 14. 



Fresh water: Scotland, Loch Leven! Lule Lapmark! Finland! Germany, Oberrohe! Canada, 

 Port Hope! 



25. N. Toulaae Pant. (1893). — V. lanceolate. L. O.ose; B. 0,021 mm. Axial area in- 

 distinct. Central area small, rounded. Strife 10 in 0,oi mm. radiate throughout, composed of 

 somewhat elongated puncta (9 in 0,oi mm.) arranged in almost straight longitudinal rows. Median 

 striffi shortened. — Pant. HI PL XII f. 196. 



Fresh water?: Hungary, Kopecz (Pant.). 



26. N. Gamma Cl. (1893). — V. lanceolate, with subrostrate ends. B. 0,o36; B. 0,oi4 mm. 

 Terminal fissures in contrary direction. Axial area indistinct; central area large, orbicular or 



