Dr. Kassai Tibor - Dr. Murai Éva szerk.: Parasitologia Hungarica 6. (Budapest, 1973)
mintha of Microtus arvalis in various European countries, but their majority discuss only a small number of helminth specimens occurring, among other small mammal hosts, of M. arvalis, or submit merely faunistic data without regard to the extensity or intensity of infection. Only those works could therefore be used for ecological appraisal in which the several authors published all helminths occurring in more than a hundred M. arvalis individuals, with an account of also the quantitative occurrence of the helminth species recovered. Data submitted by the following authors and areas were assessed (Table 3): MERKUSHEVA (1971), the European part of the Soviet Union; PROKOPIC (1971) and MITUCH (1966, 1970) ; Czechoslovakia; PURMAGA (1957) and DOROSZ (1968), Poland; DIMITROVA et al. (1962), Bulgaria; CHIRIAC and HAMAR (i960), Romania; SCHMIDT (1961 ), German Democratic Republic; BERNARD (1969), Belgium. ERHARDOVÁ (1958) examined 898 specimens of M. arvalis in Czechoslovakia. Besides some of the species mentioned in Table 3, the author recovered also Qinqueserialis quinqueserialis and Trichuris opaca . The incidence of infection of the 21 speciea of helminths recovered is not mentioned in the paper. Our own material derivea from the helminthological investigation of 197 M. arvalia specimens from Hungary, and of 829 individuals from 13 localities in Czechoslovakia (cf.Tables 1 and 2). The obtained findings were evaluated according to criteria used by KISIELEWSKA (1970) for the helminth fauna of Clethrionomys glareolus. On the basi3 of these criteria it Is possible to determine also a heterogeneous material consisting of a large number of specimens of a definite host species trapped in different localities and in different seasons. The species of helminths were determined on the basis of criteria recorded by the following authors: TRAVASSOS (1937), KIRSENBLAT (1938), SKRJABIN (1948, 1957), RAUSCH et SCHILLER (1949), SPASSKY(1951), TENORA (1964), ABULADZE (1964), DURETTEDESSET (1968), VERSTER (1969), TENORA et VAN EK (1969), BAER et TENORA (1970), BARUS, KULLMANN , TENORA (1970), TENORA et MÉSZÁROS (1971). In case the opinions on the systematic position of
