54 



p. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS 



Areas well defined 



not — 



16. 1^^'^ 



^„ J Ends of the areas convergent or parallel 

 ' \ — — — divergent . . . 



18. 



I Areas contracted in the middle 

 \ — not — — — 



21. 

 23. 



34. 

 25. 



26. I 



27. I 



.. 17. 



19. 



N. irrorata Grun. 



18. 



N. inhalata A. S. 

 . . N. fluitans Bbch. 



N. Lyra Ehb. 



N. approximata Gbev. (N. spectabilis var.). 

 ... . . 21. 



. . . . 24. 



33. 

 .... N. variolata Cl. 

 .... 23. 

 N. illustra Pant. 

 . . 28. 



N. copiosa A. S. 

 N. Sandriana Grun. 



..„ 1 Ends of the areas parallel or divergent 

 ' \ — — — convergent 



Lateral areas with a band of short striae 

 20. ■! — — pnnctate or dotted . . . 



— — smooth 



Terminal flssnres in contrary directions 



— — the same — 



(Fnncta twice as close as the stri» . . . 

 — and striae equidistant . ... 

 Stris abont 9 in 0,oi mm. . 



— — 14 - .... 

 Axial part of the valve elevated at the ends 



^- — — not — — — 



Areas with pnncta in short nndnlating rows . 



— — irregular pnncta . . 

 Areas narrow 



— broad . . 



Areas indentate in the middle 



— not — — — 

 „Q ( Areas semiorbicular . . 



\ — semielliptical 



„_ I Median portion of the areas smooth N. Stereus mwsearum Cl. 



I — — — — punctate ... .30. 



„„ / Ends rostrate N. clavata var. indica. 



\ — non — . . . 31. 



Areas with large dots N. perfecta Pant. (N. Hennedyi var. caliginosa and var. 



. NeapolUana). 



■ I — — short, nndnlating rows of pnncta . N. retieulo-radiata Br. a. Temp. 



' — — irregular pnncta .32. 



„ ■ Axial strise of 2 to 4 pnncta . . . . N. prcetexta Ehb. {N. Hennedyi var. circumsecta). 

 ' • " . . N. Schaarschmidtii Pant. 

 . N. clavata var. exul (N. Hennedyi var. constricta). 

 ' .... 34. 



.... 36. 

 N. venustissima Kith. 

 .... . N. venusta Jan. 



N. inhalata var. biharensis. 



.27. 



N. spectabilis var. hungarica and var. excavata. 



... 28. 

 . . N. oamaruensis Grun. 

 . . : . . 39. 



33. 

 34. 

 35. 

 36. 

 37. 



Valve constricted in the middle 

 not — — — 



[ 



( Axial strise of 2 to 4 pnncts 

 1 - — — 4 to 8 — 

 ( Valv 



{ 

 { 



I L. 0,( 

 I L. 0.( 



Valve rostrate . 



— non — . . 



Areas contracted in the middle . 



— not — — — 



/ Areas broad 



\ — narrow 



L. 0,047 mm. 



09 to 0,17 mm. . . 



N. clavata Greg. 



35. 



N. spectabilis Greg. 



36. 



N. Hennedyi W. Sm. 



37. 



. . N. turgidula Pant. 

 . N. irrorata Gbev. 



1. N. concilians Cl. N. Sp. — V. lanceolate, with subrostrate ends. L. 0,04.5; B. 0,023 

 mm. Lateral areas not uniting with the central area, linear or narrow lunate, not sharply defined. 

 Marginal strise 13 to 14 in 0,oi mm. Puncta about 18 in 0,oi mm., becoming more distant to- 

 wards the areas. — PI. I f. 25. 



Marine: Honolulu! 



In this form the lateral areas are separated by a row of puncta from the small central 

 nodule. It is therefore to be considered as a transitional form from the Punctatse to the Lyratae. 

 Similar forms are known from Samoa (lanceolate. L. 0,o66; B. 0,03 mm. Strise 12 in 0,oi mm.) 

 and from Madagascar. 



