Dr. Murai Éva szerk.: Parasitologia Hungarica 12. (Budapest, 1979)

of segments, extend from proximal, end of cirrus sac to the aporal dorsal excretory canal. Cirrus sac 0. 155-0. 234x0, 056-0. 093 mm. Vagina strongly developed 0.180-0.250x0.0350.055 mm. Seminal receptacle 0.220-0.280 x 0. 130-0. 170 mm. Eggs spherical, 0.044-0.050 mm in diameter. Hymenolepis diminuta (Rudolphi, 1819) (Fig. 4 a-c) Host: Rattus norvegicus. - Location: small intestine. Length 150-250 mm, maximum width 3 mm. Scolex unarmed, 0. 200 - 0.250 mm, suckers 0.080-0.096 mm in diameter. Three testes, 0.070 mm in diameter, situated in one line or one testes on the aporal side of the segment is situated a little higher. Cirrus sac 0. 240 x 0. 070 mm, seminal receptacle 0 . 300 x 0 . 150 mm . Eggs spherical 0 . 081-0 . 090 mm in diameter; oncosphere 0.036 x 0.045 mm; length of embryonal hooks 0.015 mm. Occurrence of H. diminuta in Roumania in Rattus norvegicus among other small mammal hosts were reported by CHIRIAC and HAMAR (1966), and by POPESCU et al., (1974). Hymenolepis horrid

a (Linstow, 1900) (Fig. 5 a-c) Hosts: Clethrionomys glareolus, Pityinys subterraneus, Microtus nivalis. - Location: small intestine. Length 70- 100 mm, maximum width 1.6-2 mm. Scolex unarmed 0.210 - 0.260 mm, suckers 0. 115-0 . 12 5 mm in diameter. Three testes measuring 0 . 090-0 . 130 x 0. 0 70-0 . 080 Fig. 5: Hymenolepis horrida (Linstow, 1900) A = Scolex; B= Mature segments; C = Egg mm, two are situated aporal above each other, the third poral. Cirrus with fine spines, cirrus sac 0. 150-0. 200 x 0. 030-0. 040 mm. Seminal receptacle 0. 090 mm in diameter. Eggs ovoid 0.075 x 0. 037 mm; oncosphere 0. 027 mm in diameter. This is the first report on its occurrence in Roumania. As a parasite of the Microtidae species it can be found in the whole of Central-Europe. It can easily be distinguished from other species without hooks (

H. diminuta and H. megaloon)

; its cirrus is covered by fine spikes, scolex with suckers directed strongly to the outside. Eggs elongated, ovoid with almond shaped oncosphere. For its morphology see the works of MURAI and TENORA (1973a). Hymenolepis asymmetrica Janicki, 1904 (Fig. 6 a-c) Hosts: Microtus agrestis, Pitymys subterraneus, Clethrionomys glareolus. - Location: small intestine. Length 100-150 mm, maximum width 3 mm. Scolex 0.300-0.320 mm; suckers 0. 1100. 125 mm in diameter. Rostellum 0. 045 mm with 20-22 hooks measuring 0. 018 mm of basis