Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 65. (Budapest 1973)

Kováts, D.: Anatomical investigations on the vegetative system of Lithospermum purpureo-coeruleum L.

of the Ranunculaceae type characterize the family, though he also remarks that RIDER found typical accessory cells in Cynoglossum officinale L. and in the genus Cerinthe. Besides those of Lithospermum purpureo-coeruleum L., I have not examined the stomata of other Boraginaceous plants. I think it probable that there is no uniform stoma type within the family, and the more so as I found no uniform stoma type even in Lithospermum purpureo-coeruleum L. Besides the folige leaves (Plate V, Fig. 1), I detected stomata with accessory cells also on the shoots and tunics (Rubiaceae type). Epidermal appendages (hairs) According to my investigations and observations, there are unicellular setae, cystolith hairs and other cells con tainin t cystohths on the leaves of Lithospermum purpureo-coeruleum L. I. can corroborate the statement, also by my observations on this species, that trichome and cystolith formations are antagonistic (SOLEREDER 1899). I found that the long trichomes are not or only very weakly cystohthic; the shorter ones are calciferous, and the base of the smallest ones contain true cystohths. The biggest cystohths appear, however, in the epidermal cells, which show no trace of trichome formation (SOLEREDER 1899) (Plate VI, Figs. 1-2, 4). Concerning the hairiness of the upperside and underside epiderms, I found no other difference than that the hairs are shorter and more robust on the axial epiderm (Plate V, Fig. 2), while those of the abaxial side appear more densely and are thinner and weaker (Plate V, Fig. 3). I found cystohths on both sides, though fewer and less developed ones on the undersides than on the uppersides of the leaves (Plate V, Fig. 3; Plate VI, Figs. 2, 4). According to SOLEREDER'S work (1899) this is one of the rarer cases, because, according to this author, cystolith formation is frequent on the axial epiderm and occurs only exceptionally on the abaxial one. Cystolith formation, as given also in literature, extends also to the neighbouring epidermal cells. These bulbously swollen structures, partly sunk into the mesophyll partly elevated from it, are truly conspicuous (Plate V, Figs. 2, 4). I could detect no glandular hairs hitherto — another datum substantiating HEGI'S (1927) and METCALFE & CHALK'S (1965) statements that glandular hairs appear rarely in the Boraginaceae and especially int the European species (HEGI 1927). On the other hand, SOLEREDER (1899), referring to C. SCHMIDT. SCHIBLER and MEZ, mentions also glandular hairs in some European species of the family, among others also in Lithospermum. This latter statement, as generalized for the entire genus, is not tenable according to my investigations. Leaf structure, mesophyll The foliage leaves of Lithospermum purpureo-coeruleum L. show

T a dorsiventral (bifacial) structure (Plate VI, Figs. 1-2), as established by BIDER for the genus Lithospermum (METCALFE & CHALK 1965). JODIN (1903) also considers this dorsiventral structure characteristic of the whole family. An uniseriate palisade parenchyma present under axial epidermal cells extending to nearly half of cross-section area of leaf (Plate VI, Figs. 1-2) ; longitudinal and transversal ratio pf palisade cells about 3 :1 (as given also by JODIN 1903). Cell row of palisade parenchyma and those of spongy parenchyma terminating above and below midrib (Plate VI, Figs. 2, 4), substituted in these places by 1 -3-seriate la-