B. Papp szerk.: Studia Botanica Hungarica 36. 2005 (Budapest, 2005)

Bercu, R.: Contributions to the anatomy of Asplenium ruta-muraria

Fig. 7. Cross section of the rachis tip (6 cm from the petiole base). - A: General view (xl 15). - B: Portion of the stele with a pinnulae trace (x266): Pt = pinnulae trace. Orig. The cross section, performed at 1.5 cm from the petiole base, exhibits almost the same structure but the xylem strings of the monostele are joined, towards the centre, by their abaxial protoxylem vessels (Figs 4A, B). The cross section cut at 2 cm from the petiole base shows a monofascicular stele, composed of metaxylem vessels arranged in an X-shape, characteristic to the Aspleniaceae (OGURA 1972, BlR 1957, BERCU 1998a, BERCU etal. 2000). The phloem surrounds the xylem elements (Figs 4A, B). The transection of the rachis from 2 cm up to 6 cm (from the petiole base) exhibits the same succession of tissues but the xylem vessels are in a T-shape arrangement (Figs 5A, B). Fig. 8. Cross section of pinnulae. - A: Portion of the mesophyll and midrib (x205). - B: Portion of the lower epidermis (x250): CI = chloroplasts, EC - epidermal cell, LE = lower epidermis, O = ostiole, PT = parenchyma tissue, S = stoma, Sp = sporangium, SC = subsidiary cell, ST = spongy tissue, UE = upper epidermis, VB = vascular bundle. Orig.