94 



p. T. Cr.EVK, SYNOPSIS OF THE NAVICULOID DIATOMS. 



broad, linear. Central area a transverse fascia, reaching to the margin. Strise parallel, 7 to 7,5 

 0,01 mm. — PI. If. 16. 



Slightly brackish water: Sweden (postglacial deposit of Ebbetorp in Kalmar Lan)! Mouth 

 in of Delaware! Connecticut! 



69. P. cardinalis Ehb. (1840). — V. linear, with broad, rounded ends. 

 B. 0,03 to 0,03 5 mm. Median line distinctly complex, central pores approximate, 

 comma-shaped, small. Axial area wide; central area a broad transverse fascia, 

 margin. Striae 5 in 0,oi mm., slightly divergent in the middle and convergent at 

 by a broad band. — Stauroptera cardinalis Ehb. Berl. Abh. 1840 p. 213 (accord, to 

 cardinalis W. Sm. Br. D. I PL XIX f. 166. Nav. cardinalis A. S. Atl. XLIV f. 

 p. 74 Suppl. PL A f. 5. 



Fresh water: Sweden (Lapland to Smaland foss.)! Finland! Ireland, Scotland (Loch Leven 

 Ordie Deposit), Belgium (V. H.), Italy (Livorno, Atl.), Switzerland (Brun). 



L. 0,15 to 0,2; 

 terminal fissures 

 reaching to the 

 the ends, crossed 

 Chase). Pinnul. 

 1,2. V. H. Syn. 



IX. Marluae. 



1. 

 2. 



3. 

 4. 

 5. 

 6. 

 7. 

 8. 

 9. 



10. 



11. 

 12. 

 13. 

 14. 



Artificial hey. 



j Asymmetrical . . . . . 



\ Symmetrical 



( StrisB strongly radiate . . 



\ — slightly — 



/ Axial area broad . 



\ — — narrow or indistinct . 



{Valve narrow ' 



— broad . . ... 



J Central nodule stanroid . . . 



\ — — not — 



i Central area large, orbicular . . 



\ — — a transverse fascia 



j Strije crossed by a blank band 



\ — not — — — ... 



J Valve linear 



\ — lanceolate 



) Striae 3 to 4 in 0,01 mm 



\ — 8 to 10 — — 



Valve biconstricted . 



— constricted in the middle 



— not or slightly constricted in the middle . 

 L. 0,1 mm. . ... 



L. about 0,035 mm 



Axial area indistinct . 



— — narrow 



Striae parallel 



— radiate in the middle, convergent at the ends 



2. 



... ... 3 



P. Stauntonii Gbtjn. 



P. ambigua var. Digitus A. S. 



4. 



5. 



P. ambigua Cl. 

 .P. Temperei Bbun. 

 P. bistriata Lbud. Fortm. 

 6. 



7. 



10. 



8. 



9. 



P. Trevelyana Donk. 



P. Grcenlandica Cl. 



P. excellens Cl. 



. P. rectangulata Greg. 



P. Claviculus Gebg. 



. . 11. 



12. 



lobata Grove a. Sthht. 

 . P. constricta Cl. 



13. 



14. 



. P. quadratarea A. S. 

 P. cruciformis Donk. 



Striae 12 in 0,oi mm p, cruciata Cl. 



— 15 to 20 — p. floridana Cl. 



70. P. ambigua Cl. N. Sp. — V. linear, with rounded ends. L. 0,o33 to 0,o78; B. 0,oo7 

 to 0,0 08 mm. Central nodule small, terminal nodules small, approximate to the margin. Area 

 broad, linear, not widened in the middle. Striae short, parallel, 8 to 9 in 0,oi mm., with capitate 

 terminations. — Nav. retusa Grun. A. D. p. 38 (1880). Cl. Vega p. 470 PL XXXVI f. 35. 



Marine: Lysekil (Bohuslan, Sweden, Grun.), Oldenburg (Grun.), Cape Wankarema! 



The frustule is according to Grunow, in the zone-view more or less constricted in the 

 middle and more or less broad. The connecting zone has numerous punctate longitudinal divisions 



