FIGURES 13–16 in The diatom genus Ctenophora: A discussion on its morphology, relationships, and some species

FIGURES 13–16: Ctenophora pulchella (Ralfs, BM herb.). SEM micrographs, Fig. 13, external view of whole valve; Fig. 14, external view of portion of valve, to the right a portion of the VC with undulating pi and plain 'space' for the attachment at 'central area'; Fig. 15, details of stria structure showing shape of areolae, virgae and portion of sternum; Fig. 16, external view of pole, with ocellulimbus and rimoportula. Scale bars = 1μm (Figs 15, 16), = 2μm (Fig. 14), = 10μm (Fig. 13).