PLATE 14 in The diatom genus Gomphoneis Cleve (Bacillariophyceae) from Lake Baikal, Russia

PLATE 14: SEM. Gomphoneis metzeltinii. Figs 389–391: Extenal valve views. Figs 389, 390: Whole valve views should fine striae and indistinct stigmoids. Proximal raphe ends are dilated slightly. Fig. 391. Footpole shows the rounded porelli of the apical pore field appear as condensed striae. G. capitata. Figs 392–396: Figs 392–395: Internal valve views. Figs 392–394: Entire valve views. Fig. 392: Specimen with girdle bands shows septa at the poles, wide, rectangular central area and central nodule with recurved proximal raphe ends. Fig. 393: Specimen lacking girdle bands revealing the smaller pseudosepta at the poles. The helictoglossae are evident also. Only two stigmoid openings are evident around the central nodule. Fig. 394: Specimen without girdle bands, showing pseudosepta, recurved proximal raphe ends on small central nodule, and helictoglossae at the poles. Fig. 395: Internal valve view showing only two prominent stigmoidal opening. The appear simple, without occlusions. Fig. 396: External valve view. The valve has proximal raphe ends that are prominently dilated, and has 2 types of stigmoidal openings, one larger and one smaller.