Description Fig. 6. — Hornera mediterranea n. sp., frontal side: A, bifurcated distal part of branch; B, edge of branch, note the shape of peristomes; C, branch tip without secondary calcification; D-E, two stages of secondary calcification; F, part of branch with heavy secondary calcification. Origin: A, C-E, Marseille, Riou Is., 85 m, 2/VII/1973; B, F, Riou Is., 74 m, 5/VII/1971. Scale bars: A, 400 µm; B, 100 µm; C-F, 200 µm. Photos: Jean-Georges Harmelin.