Fig. 1

Light microscopy images of live and fixed Hydra magnipapillata strain 105. a An adult polyp. The arrow indicates the basal disc. b Scheme of an adult polyp indicating details of the animal morphology. c Squeezed preparation of the foot region. The square indicates the area magnified in figure d. d The arrowheads point at individual basal disc cells. e Longitudinal section stained with hematoxylin eosin showing a general morphology of the basal disc. Inset shows the zone magnified in figure f. f Organization of basal disc cells with stained nuclei. Scale bars 1 mm (a), 100 μm (c), 50 μm (d-f). Abbreviations: ec, ectoderm; m, mesoglea; en, endoderm; pe, peduncle; bd, basal disc