Dr. Murai Éva szerk.: Parasitologia Hungarica 25. (Budapest, 1992)

of Muscardinus avallanarius likewise either stand apart or are built on those of other hosts (birds). They are small, globular and made of grass and leaves. These hosts produce little detritus: by their nest construction and way of life they do not disrupt that of the original occupant (in the case of combined nests). Thus, they leave more room for the flea fauna of the original host. The smaller difference seen in the representation of fleas characteristic of small mammals may be accounted for by a varying aggressivity and mobility (particularly a vertical migration). The autumn effect, viz. the highest representation of this group of fleas, coincides with the vertical migration i.e. with a search for, and preparation of, nest hollows in the ground or tree trunks. Besides occupying bird nests and the autumn migration, dormice can capture certain flea species through the latter's migration, particularly bird fleas during the spring season, by roaming in search of food and looking for nesting conditions, as well as through the mediation of the genus Apodemus which has a predilection for hollows. Table 5 Occurrence of flea species in dormouse nests in Slovakia (in per cent) Hosts Flea species 12 3 4 A B A B A B A B Csciurortim 62.09 41.41 90.38 72.40 97.52 98.01 42.37 54.95 C.enefdeae 0.02 C.gallinae 13.10 43.63 4.46 1.37 1.99 12.29 12.68 C.garei 0.15 0.06 0.04 C.fnngillae 1.09 0.02 C.hirundinis 0.30 0.02 0.30 C.pullatus 0.90 6.34 1.79 21.83 0.91 24.15 C.tribulis 4.12 0.79 1.24 1.34 5.58 D.gallinulae 2.11 2.40 0.03 0.56 5.93 26.80 Ct.agyrtes 0.30 0.24 Ct.assimilis 0.42 0.03 0.13 Ct.solutus 0.05 0.02 1.43 Ct.uncinatus 0.05 0.13 M.turbidus 16.69 3.82 3.19 0.30 0.23 15.25 N.fasciatus 0.06 0.07 H.orientalis 0.02 D.dasycnema 0.10 1. - Mus. avellanarius, 2. - G. glis, 3. -D. nitedula, 4. - Myoxidae; A - occurrence in genuine dormouse nests, B - occurrence in combined nests (occupied by dormice after other hosts) If we evaluate the representation of various groups or species of fleas in pure dormouse nests as such, and in nests built by dormice on those of evicted birds, the representation of C. sciurorum in the so-called pure nests is higher than in the so-called combined ones. This indicates that this species has a connection with the Myoxidae. The number of flea species characteristic of birds, particularly of hollow-nesting birds (C. gallinae, C.pullatus), is logically higher in combined nests. The contrary pattern,