56 P. T. CLEVK, SYNOPSIS OF THE NAVICULOID DIATOMS. 



Var Limyaczeki Pant. (1886). — L. O, ii; B. OjO.») mm. Striee 10 in 0,oi mm. interrupted 

 in the middle of the valve. — N. Lunyac. Pant. I p. 26 Pl. XIV f. 122. N. prcetexta Truan a. 

 WiTT Jerem. D. p. 17 Pl. IV f. 8. 



Marine: Hungary, fossil (Pant.), Hayti (Truan a. Witt.). 



N. prmtexta is a most variable species, passing inte iV. Hennedyi var. circumsecta. 



8. N. irrorata G-kev. (ISSO). — V. with parallel margins and cuneate ends, or lanceolate. 

 L. 0,09 to 0,17; B. 0,045 to 0,06 mm. Lateral areas not sharply defined, linear, with straight 

 exteriör margins, smooth. Marginal stiuse 7 to 10, pvincta 6 to 9 in 0,oi mm. Axial strise of 2 

 to 5 puncta. — Edinb. N. Pli. J. X p. 27 Pl. IV f. 1. A. S. Atl. II f. 22, 23. 



Marine: Adriatic! Sydney! Calif. gnano (Grev.), West Indies! Mexico! Campeachy Bay! Florida! 



Var. mexicana Cl. — Lanceolate. L. 0,12; B 0,053. Strise 7, puncta about 5 in 0, 01 mm. 

 — N. irrorata A. S. Atl. II f. 19. 



Marine: Gulf of Mexico (Atl.). 



Var. suistauroneiformis Grun. (1874). — L. 0,o8; 0,04 mm. Striee 7, puncta 9 in 0, 01 mm. 

 Central nodule incrassate and transversely dilated. — N. approxim. v. substaiironeif. A. S. Atl. II f. 20. 



Marine: Campeachy Bay! 



Var. ceylanica Cl. — EUiptical. L. 0,095; B. 0, 05 mm. Marginal strite 14, their puncta 

 about 21 in 0, 01 mm. Axial strise 17, tbeir puncta 16 in 0,oi mm. 



Columbo, Ceylon (Letourneur Coll.)! 



Var. ellijitica Cl. — EUiptical to elliptic-lanceolate. L. 0,075 to 0,13; B. 0,03 to 0,055 mm. 

 Areas with convex exteriör margins, convergent. Strise 9 to 10 in 0,oi mm. Puncta about 9 to 

 10 inequidistant. — Icon. n. Part I Pl. IV f. 13. 



Marine: Colon (Deby Coll.)! Gulf of Mexico! West Indies! China! Manila (Deby Coll.)! 

 Fossil: Hungary, Kekkö (Deby Coll.)! 



9. N. perfecta Pant. (1886). — V. elliptical. L. O, ne to 0,14; B. 0,o68 to 0,07 mm. Areas 

 not sharply defined, semilanceolate, with large crowded döts. Strise 9 (10 to 11 accord. to Pant.), 

 puncta about 10 in 0, 01 mm. The puncta become less crowded towards the area and are there 

 arranged in almost regular, longitudinal rows. — Pant. I p. 28 Pl. XXIII f. 207. 



Marine: Hungary, fossil! 



Var. Letournettrii Pant. (1889). — V. slightly constricted in the middle. L. 0,o8; B. 0,o32 

 mm. Strise 12,5, puncta 15 in 0,oi mm. — N. Letöur. Pant. II p. 49 Pl. XXIV f. 358. 

 Marine: Hungary, fossil (Pant.). 



10. N. venusta Jan. Ms. — V. rhombic-lanceolate. L. 0,o7 to 0,ii; B. 0,o5 to 0,o4 mm. 

 Axial part elevated. Lateral areas not sharply defined, semilanceolate with scattered puncta. Striae 

 13 in 0,01 mm. closely punctate near the margin. — Gazelle Exp. XV f. 17. 



Marine: Galapagos Islands! 



Var. intermedia Cl. — V. elliptical. L. 0,097; B. 0,052 mm. Lateral areas large, semi- 

 lanceolate, dotted on the part near the axial strite, punctate on tlie part near the marginal strii», 

 pnncta distant, gradually passing över to the marginal stria'. Marginal strise 13, their puncta 18 

 ill 0,(11 mm. Axial part less distinctly elevated. 



Marine: Mediterranean Sea (Tempére). 



This variety seems to connect N. venusta with N. perfecta. 



11. N. Barbitos A. S. (1888). — V. strongly silicious, rhombic-lanceolate, with the axial 

 part elevated towards tlie ends. L. 0,i8 to 0,22; B. 0,055 to 0, 013 mm. Lateral area.s linear, not 

 sharply detiiied, almost parallel, approximate to the median line. Stria; 12 in 0,oi mm. punctate; 

 puncta closer (about 14 in 0,oi mm.) near the margins than near the lateral area (about 9inO,oi 

 mm.), where tliey form undulating and obscurely decussating longitudinal i'ows. — Atl. CXXIX f. 5. 



Marine: Singapore! Cebu! Sumatra! Sumbava! 



