With the development of paleontology, a special branch – paleobotany – came into force in the second half of the 19th century. One of the main researchers of that time was Constantin von Ettingshausen (1826-1897), an Austrian botanist and eventually paleobotanist, who taught for a long time at various schools in Graz. Ettingshausen wrote a series of paleobotanical treatises, the most outstanding among them as far as the territory of Slovenia is concerned being the treatise on the Oligocene flora in the surroundings of Zagorje ob Savi (Die fossile Flora von Sagor in Krain). The work embraces three volumes with exceptional illustrations and descriptions. Ettingshausen also explored other sites at Socka. At the same time, however, let us not forget another outstanding paleobotanist, Franc Unger (1800-1870), who worked from Graz, too. Unger carried out a most thorough research into the fossil flora at Socka, for which it is currently assumed that it had not flourished in the Late Eocene or Early Oligocene.