Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 6. (Budapest 1955)
Dely, O. Gy.: The problem of the origin of Rana méhelyi Bolkay
The Problem of the Origin of Rana méhelyi Bolkay By O. Gy. D e I y, Budapest During the paleontological excavations of the Istállóskő and Varbó Caves (Com. Borsod, Hungary), fossil batrachian bones had also been found. As, after identification, a portion of the bones proved to be those oí Rana méhelyi Bolkay, there is a possibility now to turn views hitherto adverse in literature with regard primarily to the origin and phyletic age of the above animal in a satisfactory way into the right direction, on the ground of recent finds and material. The aim of the present paper is, therefore, not only the discussion of the views held up to now and a historical review, but to shed new light on the problem of the origin of Rana méhelyi Bolkay, by the exposed new material. When Bolkay described Rana méhelyi as the Pleistocene ancestor of Rana temporaria L. (= Rana fusca Rös.) in a paper of his (1911), he wrote as follows : »We feel fully entitled to consider Rana Méhelyi By. as the Pleistocenic ancestor of Rana fusca Rös. It is an extremely interesting fact to note, that the mammals that lived here in the Pleistocen together with the Rana Méhelyi are now confined to the arctic regions, and live there in almost unchanged uniformity whilst Rana Méhelyi on the contrary remained here and may be considered as the ancestor of our present Rana fusca Rös. having undergone great modifications in consequence of gradual changes in climatic and soil conditions. « Bolkay had known of the following collecting localities of the new species : Ó-Ruzsin, the Novi Cave, Miskolc (Puskaporos Cave), Püspökfürdő (Somlyóhegy, the collectings of T. Kormos). As specific characters, he gives generally the striking size and powerful development of the bones ; he considered, however, as the most characteristical feature by which the new species (Rana Méhelyi By.) differs from its nearest relative, Rana temporaria L., the shape of the ileum, its cervical thickness, and the conspicuous shortness and breadth of the tarsus. Though the two species can be well distinguished by the characters of the ileum 1 , he added yet the following : »It is not impossible, that the species here described is identical with the Rana fusca Rös. now living on the Tundra's. A specific distinction nevertheless appears desirable in spite of my not disposing of material for comparing from the above named region, this question therefore remains open to further investigations For the sake of comparison, Bolkay examined the ilea of several Rana species, and — 1 The concepts of Bolkay based on the tarsus cannot, as 1 have endeavoured ta show in another paper of mine (D e 1 y, 1955), be justified by recent researches.
