KONGL. SV. VET. AKADEMIENS HANDLINGAE. BAND 27. N:0 3. 35 



Var. maxima Cl. — V. less convex, lanceolate, acute. L. 0,13; B. 0,03 mm. Striae 6,5 in 

 0,01 mm. almost parallel, composed of about 7 elongated puncta, lineate, lineolse about 27 in 0,oi mm. 



Marine: Gulf of Naples (Brun's Coll.)! 



Var.? Peragalli Brun (1891). — V. rhomboidal, acute; the axial part forming a distinct keel 

 especially towards tbe ends. L. 0,08 to 0,ii; B. 0,025 to 0,030 mm. Strise 7 in 0,oi mm, slightly 

 radiate, composed of about 7 elongated puncta, crossed by fine lineolse, about 27 in 0,oi mm. — 

 N. Peragalli Beun D. espfeces n. p. 37 PI. XVI f. 12. 



Marine: Gulf of Naples! Athens (Brun). 



90. N. (AUoioneis) Monodon Brtjn (1891). — V. very convex, narrow, rhombic-lanceolate, 

 subacute. L. 0,o6 to 0,o9; B. O.oii mm. Central nodule strong, elevated with a pore in the 

 middle. Terminal nodules distant. Axial area asymmetrical narrow, slightly dilated around the 

 central nodule. Striae 6 to 8 in 0,oi mm. crossed by undulating, narrow, longitudinal areas. V. 

 in zonal view broad, slightly constricted in the middle, with obliq[uely truncate ends. Central 

 nodule forming a conical projection, perforated by a tube. Striae composed of elongated puncta. 

 — Diat. espfeces n. p. 36 PI. XVI f. 8. 



Marine: Japan (Brun)! 



This is one of the most remarkable naviculoid diatoms, diverging from all other known 

 forms by its central nodule, forming a conical, perforated projection on the outside of the valve. 



91. N. distans "W. Sm. (1853). — V. lanceolate, gradually tapering from the middle to the 

 obtuse ends. L. 0,o9 to 0,i3; B. 0,oi7 to 0,0 2 mm. Axial area gradually dilated towards the 

 middle, where it expands to a large, rounded quadrate space. Striae. 5 to 6 in 0,oi mm., radiate 

 throughout, strongly lineate ; lineolae 21 in 0,oi mm. — Finn, distans W. Sm. B. D. I p. 56 

 PL XVIII f. 169. N. distans A. S. Atl. XL VI f. 11 to 14. N. S. D. II f. 38 (without name). 

 V- H. Syn. p. 87 SuppL, PI. A f. 18. N. dist. v. borealis Grun. A. D. p. 38 PI. II f. 42. 



Marine: Frans Josefs Land (Grun.), Spitsbergen! Finmark! Greenland! North Sea! 

 JSF. distans seems to belong to the Arctic Sea and Northern Atlantic. I have not seen 

 typical specimens from other seas. 



92. N. subalata Grun. (1880). — V. lanceolate, obtuse. L. 0,o8; B. 0,02 mm. Median line 

 with approximate central pores and distant terminal nodules. Axial area linear distinct. Central 

 area large, somewhat transverse. Striae 6 in 0,oi mm. radiate throughout, transversely lineate; 

 lineolae 22 in 0,oi mm. The striae in the middle do not reach the margin, so that the valve 

 seems there to be bordered by a hyaline rim. — A. D. p. 38. Icon. n. PI. I f. 32. 



Marine: Seychelles (Van Heurck Coll.)! 



An original sketch by Grunow agrees perfectly with the specimen in Van Heurck Collec- 

 tion, which has distinctly lineate striae. According to Grunow they are smooth. 



93. N, salva A. S. (1876). — V. elliptic-lanceolate, sometimes with slightly triundulated 

 margins and subrostrate ends. L. 0,osa to 0,06; B. 0,02 to 0,022 mm. Median pores approximate; 

 terminal nodules distant. Axial area narrow, linear. Central area large, quadrate. Striae 8 in 

 0,01 mm. radiate throughout. — Atl. XL VI f. 23. 



Marine: Balearic Islands! Campeachy Bay (Atl.), Florida! 



94. N. opima Grun. (1867). — V. elliptic-lanceolate, with rounded, obtuse ends. L. 0,o6 

 to 0,1 1; B. 0,017 to 0,025 mm. Central pores approximate; terminal fissures almost straight, 

 large, at some distance from the ends of the valve. Axial area broad, linear. Central area large, 

 orbicular. Striae 6 to 8 in 0,oi mm., more distant in the middle; strongly radiate throughout, 

 lineate; lineolffi 24 in 0,oi mm. — N. fortis var.? opima Grun. Novara p. 100 PI. 1 A t 13. N. 

 opima A. S. Atl. XLVI f. 24, 25, 26. N. fortis A. S. Atl. XLVI f. 19, 20, 21, 22. 



Marine: Greenland! Davis Straits! Grip in Norway! Baltic (Atl.), Barcelona! 



