Szekessy Vilmos (szerk.): A Magyar Természettudományi Múzeum évkönyve 56. (Budapest 1964)

Rásky, K.: Studies of Tertiary plant remains from Hungary

ses between the lobes are wide, the lobes terminate in rather sharp points. The margin is dentate, but the sharp teeth are not uniform, being spaced irregularly. From the base of the leaf, a midrib and two lateral veins extend into the apex of the lobes. The midrib and the lateral veins emit tertiary veins, among which the blade is filled in by a network. No petiole remained. The leaves are slightly coriaceous. The lateral lobes of the two damaged specimens extend rather more laterally. Remarks: The leaf remains might be compared to those described by HEER under the name Acer trilobatum from the Swiss flora (1859, p. 47, and p. 197, Taf. 2, Figs. 3 -4, 6, 8, and Taf. 110 -116). Of the Acer trilobatum leaves, showing considerable polymorphism, of the Swiss flora, the leaf remains shown on Taf. 110, Fig. 17, Taf. Ill, Fig. 19, and Taf. 113, Fig. 5, stand the closest to the Ipolytarnóc specimens. The fossil leaf remains of Acer trilobatum had been found in nearly all Tertiary fossil floras of Europe, and are especiallv frequent in the younger Tertiary floras. The Acer trilobatum leaf, described by HANTKE (1945, p. 76, Taf. 13, Fig. 10) from the Miocene of Schrotzburg, is larger than the Ipolytarnóc specimens. WEYLAND lists their occurrence from the Rott flora, KRÄUSEL from the Mainz-Kastel flora. The species was excavated from the fossil floras also of Bilin, Sagor, Radoboj, Italy, France, Roumania, and Hungary (ANDREÁNSZKY, PÁLFALVY). Nor do the various Acer species miss from the fossil floras of North America and Japan. In Japan, they occur from the Paleogene to the Pleistocene (TANAI & SUZUKI, 1960). The leaves of Acer florini Hu & CHANEY differ from the Ipolytarnóc finds. Comparison with recent species : The leaves of Acer trilobatum (STERNB.) A. BR. are brought into connection with those of Acer rubrum L. This species extends today from Canada to the southern part of North America, frequenting wet habitats. TANAI & SUZUKI compared the leaves of Acer florini Hu & CHANEY with those of Acer mono MAXIM., and Acer buergerinum MIQ., ranging in SE Asia. GRANGEON compared his Acer leaves from France with the recent Acer tucheri DUTHIE of China. The lobes are longer and more expanded on the dentately lobate leaves of this latter species than on the Ipolytarnóc leaves. Acer trilobatum (STERNB.) A. BR., fruits (Plate XII, Fig. 7) Description : The impressions of two whole double samaras were found. The length of the fruit is 2.3 cm, the width of the wings 0.7 cm, the length of the extant stalk 0.5 cm. The dorsal surface of the fruit wings are straight, the apices rounded. The venation of the wings is parallel on the dorsal surface, then arching, and forking, it extends toward the ventral side. The seeds are oval, 6—7 mm long. Above the seeds, the basal section of the samara attenuates. Remarks: The Acer trilobatum fruits of Ipolytarnóc also well resemble those described by HEER from Switzerland. WEYLAND, too, lists the fruits from the fossil flora of Rott (1937, p. 106). KRÄUSEL worked out a considerable number off Acer fruits from the Aquitanian flora of Mainz-Kastel, classifying them into four groups. Into the first group belong the Acer trilobatum type samaras, and the Ipolytarnóc specimens can be satisfactorily relegated to this form group (1938, p. 74, Abb. 24). However, the Ipolytarnóc Acer fruits differ from the one described by UNGER under the name Acer trilobatum, from Abaújszántó, Hungary (1870, p. 11, Taf. 4, Fig. 2, Collect, nr. 61. 217. 1) by this latter having much wider samaras medially, and the wing apex not rounded^ Nor do the Ipolytarnóc remains resemble the characteristical fruits of Acer jurenaki STUR, collected by the present author also in Tállya (1952). There are none among the several Acer fruits, published by TANAI & SUZUKI (1960, Taf. 9) from the Miocene of Japan, identifiable with the Ipolytarnóc remains. Comparison with recent species : Also the fruit remains of Acer trilobatum are connected with those of the recent Acer rubrum L. The species inhabits the Atlantic coasts of North America, and the shores of the Mississippi.