'.. PLATE 40 

 FIG. PAGE 



1 Caloneis liter (Win. Sm.) Cl 81 



2 Anomoeoneis sphserophora (Kuetz.) Cl 80 



3 Nitzschia spathulata Breb ' 120 



4 Stauroneis ? abnormal 89 



5 Xavicula ? abnormal 101 



6 Podocystis adriatica Kuetz 129 



7 Xitzschia dissipata (Kuetz.) Grim 120 



8 Cymbella ventricosa Kuetz. (zone view) 62 



9 Navicula radiosa Kuetz. (zone view) 94 



10 Detail of Rhabdonema arcuatum (Lyng.) Kuetz 35 



11 Diatoma anceps (Ehr.) Kirchn. (containing chromatc- 



phores) 42 



12 Coscinodiscus asteromphalus Ehr. (trans, section, after 



Pelletan) , 23 



13-14-15 Transverse section (diagram) of Pinnularia showing 



straight, oblique and grooved raphes 101 



16 Transverse section (diagram) of Biddulphia favus show- 



ing inner punctate stratum (after Deby) 31 



17 Transverse (ideal) section of Surirella 124 



18-19 Transverse (ideal) section of Pinnularia, before and 



after division 101 



20 Transverse section of Nitzschia linearis (Ag.) Wm. Sm. . 122 



21 Transverse section (diagram) of Xavicula 89 



22 Transverse section (diagram) of Cymbella 60 



23 Transverse section (diagram) of Amphora 65 



