O. G. Dely szerk.: Vertebrata Hungarica 8/1-2. (Budapest, 1966)

Topál, Gy.: Some observations on the nocturnal activity of bats in Hungary 139-166. o.

VERTEBRATA HUNGARICA MUSEI HISTORICO - NATURÁLIS HUNGARICl Fasc 1-2. 1966. Tom. VIII. Some Observations on the Nocturnal Activity off Bats in Hungary By Gy. Topéi Zoological Department of the Hungarian Natural History Museum, Budapest In the last few decades, scientific interest in bats had increased all over the world, and, in the wake of painstaking studies, the results of detailed investigations concerning their life cycles had been published in numerous papers. However, even these contributions often submit but generalities when they record, e.g., that this or the other species takes to the wing „at dusk" or „immediately after sunset", leaving its shelter „after other species", or returns „directly before sunrise", etc. Due to a host of causes, observations of this kind made directly in the field come up against numerous difficulties, though their importance, aside of laboratory researches, is indisputable in the study of the daily rhythm of these interesting mammals. In this field, we owe the first observations to ALTÜK (1), who became aware of a certain regularity between the evening hunting flight of the bats and the time of sunset, finding in it certain differences with regard to the observed species. Among the recent studies, important are GrAISLER*s (5) work on Rhinolophus hipposidero

s

. NYHOLM 's (15) records concerning Myotls mystacinu

s, MISLIN's (14) and KOLB's (8,9) observations on Hyotis myoti

s, EISENTRAUT'

s (4) researches on Piplstrellus pipistrellu

s and Eptesicus sero-