Dr. Holló Ferenc szerk.: Parasitologia Hungarica 3. (Budapest, 1970)
the one at Surány produces mosquitoc only at a rather constant 500 cm water level of the Danube, when the ground-water erupts along an extensive area. This latter place would be suitable for the application of NOVAK'S method (1966) who reduced the number of mosquitos to the minimum by a single chemical intervention in the breeding habitat along the river Morva during the spring. Oui" experiments (1960-61) have justified N0VÁK-*s contentions ,with the reservation that his method can be applied only in the case of larvae breeding in pools originating from groundwater eruptions or rainfall. In the case of inundations hocked up with the Danube,drift of silting had soon covered the poisoned area, or the insecticide was washed away (SZABÓ, 1964). These considerations, outlined above, instigated the observation of the mosquito breeding sites of also the Csepel Island, concurrently with the alterations of the water level. This was the more necessary as there have been founded two significant industrial settlements near the Island - well within flying distance of the mosquito species breeding in inundation territories - namely Százhalombatta and Dunaújváros. Furthermore, Csepel is becoming a weekend and holiday recreation area or a summer resort. The more important mosquito breeding sites on the Csepel Island are in the neighbourhood of Tököl,Szigetujfalu, and Makád. Their combined surface area is about 200-500 cadastral yokes even at a medium water level. At high water, this area may extend to 3000-5000 cy. The total surface of the breeding sites becomes restricted, also in the Island, to about one-sixth of the original extent after the passing of high water (except some parts of the breeding sites near Makád). The significant breeding sites of the stretch between the southern end of the Island and Dunaföldvár are in the neighbourhood of Szalkszentmárton, opposite Dunaújváros, and on the Dunaföldvár Isle. Both are very extensive, of several hundreds of cadastral yokes. This zone is characterized by the survival
