A massive basal scales of N. clavata B thin, imbricate coenenchymal scales of N. fordi C thick, mosaic arranged coenenchymal scales of N. mosaica D individual thick coenenchymal scale of N. mosaica with a finely granular outer surface E complexly ridged coenenchymal scale of N. muzikae F single medial coenenchymal ridge of N. pauciflora G sail scale of N. spectabilis H serrate distal margin of body wall scales of N. bowersi I spinose body wall scales of N. horrida J adaxial body wall scales of N. dampieri K polyp pair of N. leilae showing extensive cowl and serrate distal edges of body wall scales (from Bayer, 1951).