Hannaea inaequidentata, initial frustules and pre-normal vegetative valves, LM 70, 71 two initial frustules, note nonexistent (undeveloped) sternum and irregular valve face 72–78 seven pre-normal vegetative valves showing seven irregular valve shapes: almost straight with undulate valve margins (72), sigmoid with constricted two middle margins (73), double S-shaped with one middle margin constricted (74), parallel middle margins with one half of valve straight and the other deflexed (75), swollen middle part with almost straight valve (76), arcuate with globular middle part (77), and nearly normal but distinctly arcuate (78).