Ceterach officinarum, DC.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1964, Flora Europaea - Volume 1. Lycopodiaceae to Platanaceae, Cambridge University Press : 17

1. C. officinarum DC. in Lam. & DC., Fl. Fr. ed. 3, 2: 566 (1805).

Leaves 3-25 cm, persistent, oblong; petiole short, as long as lamina, covered with scales; lamina greyish to dark green above, covered with light brown, overlapping scales beneath; leaf-segments alternate, ovate or oblong, 9-12 on each side, entire or crenate, rounded at the apex. Sori c. 2 mm. Mean spore-length 41-48 g. 2n = 144. Dry rocks and walls. W., S. & C. Europe, northwards to Scotland and S. Sweden, eastwards to Krym. All except Az Da Fa Fe Is N o Rs (N, B, C, W, E) Sb; only as naturalized alien in Po. A taxon from S.E. Europe, differing from 1 in chromosome number (2« = 72) and mean spore-length (32-39/0, has recently been described, as Asplénium javorkeanum , by G. Vida, Acta Bot. Acad. Sci. Hung. 9: 197 (1963).