Bacillariophyceae: (diatoms)

Agardh Amphora apical axis areolae auxospore Axial area narrow Biddulphia Boyer breadth Brébisson Cells solitary Cells united Cells usually central nodule centre Chaetoceros chain formation Chromatophores Cleve Cleve Pl colonies common composed of numerous constricted convex Coscinodiscus costae cuneate Diameter of valve diatoms Dimensions Diploneis Distribution Donkin Ehrenb Ehrenberg elongated English Channel Frustules furnished genus Girdle composed girdle view Gran Gregory Grunow Hendey Hustedt hyaline intercalary bands keel Kützing Lebour Length of valve linear-lanceolate loculi micr mucous Navicula Nitzschia nodules small North Sea North Sea coasts Peragallo pervalvar axis plankton PLATE Pleurosigma polar nodules protoplast pseudoraphe raphe Raphe straight rectangular in girdle resting spores Rhizosolenia rostrate rounded apices Sect setae showing chromatophores side sigmoid Smith spines striae punctate structure Surirella Type locality united to form valve mantle valve margin Valve surface striate valve view Valves broadly Valves circular Valves elliptical Valves lanceolate Valves linear ventral margin weakly siliceous