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



Var LunifacseJci Pant. (1886). — L. 0,ii; B. 0,05 mm. StricV 10 in 0,oi mm. interrupted 

 in the middle of the valve. — N. Liin-i/ac. Pant. I p. 26 PL XIV f. 122. N. prrftixfu Truan a. 

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



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



N. prcetexfo is a most variable species, passing- into K. Hennedyi var. nrcunisccta. 



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

 L. 0,09 to 0,17; B. 0,04 5 to O.ofi mm. Lateral areas not sharply defined, linear, with straight 

 exterior margins, smooth. Marginal striiv 7 to 10, puncta 6 to 9 in 0,01 mm. Axial striie of 2 

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



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



Var. mcxicana Cl. — Lanceolate. li 0. 12; B 0,o.'s.3. Strife 7, puncta about o in O.oi mm. 

 — iV. irrorata A. S. Atl. II f. 19. 



Marine: Gulf of Mexico (Atl.). 



Var. snhsfdnroneiformis Grun. (1874). — L. 0,08; 0,04 mm. Strine 7, puncta 9 in 0,01 mm. 

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



Marine: Campeachy Bay! 



Var. ceylanica Cl. — Elliptical. L. 0.095; B. 0,o5 mm. Marginal strife 14. their puncta 

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



Columbo, Ceylon (Letourneur Coll.)! 



Var. elUpHca Cl. — Elliptical to elliptic-lanceolate. L. 0,075 to 0,13; B. 0,o3 to 0,055 mm. 

 Areas with convex exterior margins, convergent. Stria'. 9 to 10 in 0,oi mm. Puncta about 9 to 

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



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

 Fossil: Hungary, Kekko (Deby Coll.)! 



9. N. perfecta Pant. (1886). — V. elliptical. L. 0,iit; to 0,14; B. 0,008 to 0,07 mm. Areas 

 not sharply defined, .semilanceolate, with large crowded dots. Striee 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 PI. XXIII f. 207. 



Marine: Hungary, fossil! 



Var. Letonrneurii Pant. (1889). — V. slightly constricted in the middle. L. 0,o8; B. O.032 

 mm. Stria} 12,5, puncta 15 in 0,oi mm. — N. Lefonr. Pant. II p. 49 PI. XXIV f. 358. 

 Marine: Hungary, fossil (Pant.). 



10. N. veuusta Jan. Ms. — V. rhombic-lanceolate. L. 0,07 to 0, 11; B. 0,o5 to 0,o4 mm. 

 Axial part elevated. Lateral areas not sharply defined, semilancteolate with scattered puncta. Strise 

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



Marine: Galapagos Islands! 



Var. itifcrmedia 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 neai' the marginal stria;, 

 puncta distant, gradually passing over to the marginal stria-. Marginal stria; 13, their puncta 18 

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



Marine: Mediterranean Sea (Tempere). 



This variety seems to connect N. venustn with N. prrfertu. 



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

 part elevated towards the ends. L. 0,i8 to 0,22; B. 0,o55 to (),oi;i mm. Lateral areas linear, not 

 sharply defined, almost parallel, approximate to the median line. Strife 12 in 0,o 1 ram. punctate; 

 puncta closer (about 14 in 0,oi mm.) near the margins than near the lateral area (about 9in0,oi 

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



Marine: Singapore! Cebu! Sumatra! Sumbava! 



