Dr. Murai Éva szerk.: Parasitologia Hungarica 13. (Budapest, 1980)

MATERIAL AND METHODS Samples of the test material were derived from the following countries and hosts: Albania, Bulgaria, Czechoslovakia, Germany, Denmark, England, France, Finland, Greece, Hungary, Ireland, Italy, The Netherlands, Poland, Rumania, the USSR and Yugoslavia mainly from domestic (cattle, sheep, buffalo, goat) and to a lesser extent from wild (roe deer, red deer, fallow deer, rein deer and moose) ruminants. Altogether more than five hundred sections of the different species have been prepared for examination. Besides these, sections of the relevant species of NÄSMARK' s collection and of the collection of the Natural History Museum, Berlin; type specimens of WILLMOTT's species as well as sections of the material of MIHAILOVA et al. were also available. RESULTS AND DISCUSSION Having examined the amphistome material and the relevant literature we regard the following species to be valid. Synonyms, listed under the species cover those reported from Europe up to now. Paramphistomum cervi (Zeder, 1790) Syns: Paramphistomum (= Liorchis) hiberniae Willmott, 1950 P. leydeni Näsmark, 1937 P. (= Liorchis) scotiae Willmott, 1950 The first description of this species of scientific value was given by FISCHOEDER (1903) and those specific features used in differentiation, the presence of the papillae in the anterior part of the pharynx and the muscular elements in the genital opening were included in his description. P. cervi was characterized histo-morphologically by N A SM ARK (1937) as a species in having Liorchis-type of pharynx, Gracile-type of genital opening and Paramphistomum-type of acetabulum, with his remark that the pharynx has no papillae and the musculature in the genital opening is emterily absent. Yet, these features could be observed in the single slide of P. cervi found in NÄSMARK's collection, whereas the papillae are in the state of movement of the detachment, probably owing to its treatment in water before fixation (Figs. 1-2). The structure of the genital opening of the type of P. leydeni (

Epiclitum) as it was described by NÄSMARK (1937) (Figs. 3-4) can also be brough into connection with the prefixative soaking of specimens. Since, under the influence of water the genital opening enlarges, the radial muscles become loose and thick (Fig. 5), the ability to bind stains decreases and later the radial musculature is difficult to see (Fig. 6). Accordingly, such a procedure before fixation can transform the same type of genital opening into a type with distinct radial muscles (Epiclitum-type of P. leydeni sensu NÄSMARK (1937), (Fig. 5) or an other one without musculature (Gracile-type sensu IsÏASMARK (1937), (Fig. 6) as our experiment* and observations indicate. The structure of the pharynx of P. leydeni (Fig. 7) was found to be similar to that of P. cervi. Specimens of both P. cervi and P. leydeni found in NÄSMARK' s collection were soaked, proved by the empty and enlarged parenchymal cells (Figs. 1-4). In our preparations of P. cervi from different hosts it was found that the pharynx was always furnished with papillae (Fig. 8) and the genital opening with radial muscles, more or less developed provided they were not treated in water for a long time (less than four hours) (Fig. 9); thus, these structural elements are normal components of these organs. WILLMOTT (1950) described two new species - Paramphistomum hiberniae

, P. scotiae - found in the test material originated from Ireland, The Netherland and Scotland. Both species have a modified Liorchis-type pharynx, the genital opening of P. hiberniae was designated as Ichikawai- and of P. scotiae as Epiclitum-type. VELITCHKO (1966) having examined WILLMOTT' s original material found that P. hiberniae has the same type of genital opening (Epiclitum) as P. scotiae has and she, contrary to WILLMOTT (1950) designated the pharynx of the former species as pseudo-Liorchis-type. According to WILLMOTT (1950) the modified Liorchis-type pharynx has well-developed middle and exterior circular muscles in the posterior two thirds of the pharynx and inconspicuous ones in the anterior third. In NÄS-