41 

 variable, sepia shalloxv, usually snpcrjiciaì and straight, frustule usually 

 Avith thicìt walh, stipes short. 



1. L. dubia Grun. 



2. — var. adriatica Mer. 



3. — var, finmarchica Grun. 



4. — var. latior Mer. 



5. L. politica Mer. 



6. L. ovuliun Mer, 



7. L. adriatica Mer, 



8. X. anglica (Kùtz,) Grun. 



9. 7v. Oedipus (Kùtz.) Grnn. 



10. L. Jiirgensii Ag. 



11. — var. intermedia Grnn. 



12. — var. chersouensis Grun. 

 i3. — var. capensis Grun. 



14. L. cousiriclu Grun. 

 i5, L. Reichardti Grun. 

 .'' 16. /., penna gna Mer, 



III. Debiles. — Valve usually davate, abruptly attenuateci, with 

 lo\ver part very narrow, superior apex usually acute, pseudoraphe 

 fine, sepia shallozu, with septal puncta distinct, round. Usually de- 

 licate forms, with thin walls. Endochrome with granules more or 

 less irregular or elongated. Sessil or on short stipes with differen- 

 tiated axial part. 



i. L. debilis (Kùtz.) Grun. 



2. L. haslala Mer, 



3. — var. clavata Mer. 



4. L. capitata Mer. 



5. L. infiala Mer. 



ó. — var. intermedia Mer. 



7. L. parasitica Mer. 



8. L. membranacea Mer. 



9. L. remuloides Mer. 

 10. L. remulus Grun. 



