S. Mahunka szerk.: Folia Entomologica Hungarica 46/2. (Budapest, 1985)

of 25 I 2 0 C, which then were collected in separate glass vials with indication of the time of their emergence (Table 1). Wide-ranging observations were made on cattle while grazing or in their corrals towards the exploration of the distribution of the fly imagos over their bodies and also on flies sitting on poles and bars of corrals or other landmarks. Flies were watched while sucking fluids on fresh cattle droppings, urine and saliva of cattle left on stubs of grass. We managed to establish laboratory stocks of Musca autumnalis and Musca osiris in the laboratory of the Veterinary University (Budapest). In the course of maintainance of the laboratory stock of these two species we had possibilities for making another series of Interesting observations. Results and discussion In the present series of investigations 5767 specimens of 36 dipterous species were reared from cattle droppings from the end of May till the end of October; their data are summarized in Table 1. The numbers and species-composition of the imagos caught on the bodies of cattle and in their environs are given in Tables 2 and 3 (4461 and 1574 specimens, respectively). An evaluation of the data involved in the three tables from the point of view of the dominant species or of the species of veterinary importance can demonstrate unambiguously that neither the real size of the populations nor the real relationships of their dominance can be judged on the basis of collectings on cattle or in their environs. We can determine the true relationships by the far more time-consuming and very laborious method of rearing flies from droppings only; for rather details see below on the species Musca autumnalis and Haematobia irritans

. Numerous papers have been published (let us mention here only the book of IVASHKIN and KHROMOVA (1983)), in which far-reaching conclusions are formed on the species-composition and dominance of secretophagous and hematophagous flies pestering cattle, based merely on materials of low numbers of specimens netted on cattle. On the basis of the data involved in Table 2 one can conclude that in consequence of the overdomlnance of Haematobia irritans, it is necessary to collect several hundreds or even approximately a thousand of dipterous imagos for an Individual a single sample if we want to have a little chance to catch at least one specimen of - not even a really rare - species of the other flies pestering cattle. The differences in the species-composition of the 36 species found in the present studies are not significant when comparing them to the results of earlier studies of this kind in Hungary (e. g. Aranyosgadány, 1969: 36 species, 21 spp. of them identical with those in the present 36 spp.; PAPP (1976) published on rearing of 30 species from cattle dropping samples collected in six different areas of Hungary, 17 species of the latter series are Identical with the present 36 spp., a complete identity of the dominant species is found). But if these Hungarian data are compared to those of the investigations on the British Isles (BALL, 1982, TITCHENER et al., 1981, HILLERTON et al., 1984), we can find even different dominant species, and what is more, GREGOR and DUSBÂBEK' s (1982) results from collectings in Czechoslovakia are essentially different from ours. For instance, the low abundance of Hydrotaea irritans in the Hungarian materials is rather striking. Therefore, the species-composition of the larval populations in cattle droppings shows considerable differences from area to area even In Europe (cf. PAPP, 1976), that statement is valid not only in the general sense but also for any given species of veterinary importance. An instructive consequence of all these is, that somewhere a practical application of any good results gained elsewhere in the control of cattle pestering flies must be preceded by a taxonomlcal survey, whose results can make that application reasonable. Obligate coprophagous species In Hungary specimens of numerous dipterous species develop in cattle droppings on pastures from the spring till autumn whose imagos feed exclusively on fresh cattle dung, or they supplement this diet at most with nectare or flower pollen, etc., but these imagos are very seldom, if ever, on the bodies of cattle (e.g. the imagos of Paregle cinerella collect warmth on cattle - first of all on their legs - in cooler weather, see Table 2: No. 15). The specimens of the sepsid species Sep sis thoracica (Robineau-Desvoidy, 1830) occurred at/embodies the highest relative abundance among these obligate coprophagous species. Other seven species of the family Sepsidae were found, of which the species Sepsis biflexuosa Stróbl, 1893 seems to be the most significant. In Hungary 12-15 sepsid species develop in cattle froppings, and owing to their high dominance, the representatives