S. Mahunka szerk.: Folia Entomologica Hungarica 58. (Budapest, 1997)

of animals running up to several thousands. Besides we preserved various worms and fixed a few water samples, too, for microcrustaceans and other aquatic organisms. This side activity, accompanying our project, finally yielded a valuable material which will enrich the collections of the Hungarian museum. DESCRIPTION OF THE RESEARCH ACTIVITY Collecting trips 1. Guerrero State. The first trip was made on the 17th of June by accompanying the collecting and study tour organized by the Botanical Department of UNAM. We had the good fortune to use the bus of the university. Thereby day by day we had the easy access to the collecting places, and at the same time in Chilpancingo (the capital of the state) we could work and preserve our materials under normal conditions. We spent here four days and were acquainted to following types of vegetation: 1.1. Warm temperate deciduous forest with evergreen elements, at a height of 1500-1900 m. In fact this somewhat corresponds to the hairy oak zone of the Balkan Peninsula, comprising the species of Quercus, Ostrya, Leucothoe and Crataegus, but at the same time one also finds here subtropical-tropical semi-deciduous species of trees and shrubs, like Bursera, Byrsonima, Croton. To make the assortment even more versatile here we found tropical-subtropical lianas, epiphytes, ferns and other pteridophytes. 1.2. In the same zone we found semi-evergreen scrub forest, at the same altitude formed by the genera Quercus, Juniperus, Pistacia, Rhus, Zanthoxylum on the rocky faces with southern exposition, resembling somewhat in structure the Mediterranean macchia or the Californian chaparral. Furthermore, evergreen trees of tropical origin (Calohortus, Lysiloma, Stemmadenia, Thevetia) were also here. 1.3. On the limestone tropical karst huge individuals of Ceiba aesciilifolia, Sterculia apetala, Ficus padifolia were emerging from the canopy comprising semi-deciduous trees of Sideroxylon capiri, Swietenia humilis, Bursera arborea, Cedrela mexicana, Celtis monoica, Spondias mombin having well-developed layers of scrubs and lianas. The soil samples were extracted in the laboratory (cf. list of localities). The electric lighting of the extractors helped to secure more material than otherwise would have been expected in a week. 2. Selva Lacandona. We embarked on our second trip on the 24th of June. By touching the capital, Tuxtla Gutierrez of the Chiapas State, from the town Comitan we flew in a hired plane to Chajul, a small village by the border of Guatemala. Traversing the river Lacantun we finally reached our real collecting area, the world's biggest tropical rain forest reserve, called Selva Lacandona. Its entire area is 2,000,000 hectares of which 321,200 hectares is a biosphere reserve, named Montes Azules. Its lowest point of elevation is 60 m in the valley of Rio Usumacinta. From here the Chapanea Plateau is rising up to its highest point of 2450 m. The mountainous area covered by virgin forests has only been partly explored. On the bank of Rio Lacantun was our base, the Biological Station of UNAM. Here we made experiments and collectings in the following vegetation types. 2.1. Right by the Chajul Station the area is flat with tropical rain forest, where huge trees rise up in the sky having two canopy layers. There are lianas and epiphytes, small palms as under storey and tall forbs in the herb layer.