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



Var Lunyaczehi Pant. (1886). — L. 0,ii; B. 0,05 mm. Stria", 10 in 0,oi mm. interrupted 

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

 Witt Jerem. D. p. 17 PI. IV f. 8. 



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



N. prcetexta is a most variable species, passing into N. Hennedyi var. circumsecta. 



8. N. irrorata Grev. (1859). — V. with parallel margins and cuneate ends, or lanceolate. 

 L. 0,09 to 0,17; B. 0,04 s to 0,06 mm. Lateral areas not sharply defined, linear, with straight 

 exterior margins, smooth. Marginal strise 7 to 10, puncta 6 to 9 in 0,oi mm. Axial striae of 2 

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



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



Var. mexicana Cl. — Lanceolate. L. 0,12; B 0,o53. Striae 7, puncta about 5 in 0,oi mm. 

 — N. irrorata A. S. Atl. II f. 19. 



Marine: Gulf of Mexico (Atl.). 



Var. svbstauroneiformis Grun. (1874). — L. 0,o8; 0,04 mm. Striae 7, puncta 9 in 0,oi mm. 

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



Marine: Campeachy Bay! 



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

 about 21 in 0,0] mm. Axial striae 17, their puncta 16 in 0,oi mm. 



Columbo, Ceylon (Letoumenr Coll.)! 



Var. elliptica Cl. — Elliptical to elliptic-lanceolate. L. 0,075 to 0,13; B. 0,o3 to 0,o55 mm. 

 Areas with convex exterior margins, convergent. Striae 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, KekkB (Deby Coll.)! 



9. N. perfecta Pant. (1886). — V. elliptical. L. 0,ii6 to 0,14; B. 0,o68 to 0,07 mm. Areas 

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

 puncta about 10 in 0,oi 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. Letourneurii Pant. (1889). — V. slightly constricted in the middle. L. 0,o8; B. 0,o32 

 mm. Striae 12,5, puncta 15 in 0,oi mm. — N. Letoiir. Pant. II p. 49 PL XXIV f. 358. 

 Marine: Hungary, fossil (Pant.). 



10. N. venusta Jan. Ms. — V. rhombic-lanceolate. L. 0,07 to 0,ii; B. 0,o5 to 0,04 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 striae, punctate on the part near the marginal striae, 

 puncta distant, gradually passing over to the marginal striae. Marginal striae 13, their puncta 18 

 in 0,01 mm. Axial part less distinctly elevated. 



Marine: Mediterranean Sea (Tempore). 



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 the ends. L. 0,i8 to 0,22; B. 0,055 to 0,oi3 mm. Lateral areas linear, not 

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

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

 mm.), where they form undulating and obscurely decussating longitudinal rows. — Atl. CXXIX f. 5. 



Marine: Singapore! Cebu! Sumatra! Sumbava! 



