FIGS 19–25. Phylactella megarensis sp. nov. All from S. Marcellino section, sample 7: inferred depth 50–60 m, except for figure 25: to sample 2: inferred depth 40 m. (19) Sheet-like portion of a colony with sterile and ovicelled zooids. (20) Zooids showing well-developed peristomes. (21) Detail of the depressed primary orifice showing the arched lyrula and the stout, roundish condyles. (22) Primary orifice slightly tilted to show the beaded anter, partially hidden by peristome. (23) Close-up of a condyle with its crest-like barren proximal part. (24) Detail of an ovicell protected by a nearly complete, convolute and scalloped, peristome. (25) Ancestrula fitting between two echinoid tubercles, giving rise to a unique distal zooid. Scale bars: 500 Mm (19); 200 Mm (20, 25); 50 Mm (21, 22); 10 Mm (23); 100 Mm (24).