Fig. 6 in The morphology and fine structure of the Ordovician Cephalodiscus-like genus Melanostrophus

Fig. 6. Melanostrophus fokini Öpik, 1930; Upper Ordovician (Kukruse Stage, C β), Ubja (Estonia); ZPAL Pb 6/1. SEM micrographs. A–C. De2 tails of ectocortex. Abbreviations: b, bundle of cortical fibrils; cf, cortical fibril; h, homogenous material within the cortical tissue.