Dr. Kassai Tibor - Dr. Murai Éva szerk.: Parasitologia Hungarica 8. (Budapest, 1975)

Reproductive system. The first testes are found 3-4 mm behind the scolex, the last ones at the anterior pole of the cirrus pouch. The anterior testes are smaller (120-140 p in diameter) than the posterior ones (170-250 p in diameter) (Fig. 9-10). The cirrus pouch is ovoid, and 800-960 x 640-720 p in size. The cirrus is "folded" in the posterior two thirds of the pouch in the inactive state, but forms a 640 u long structure with muscular walls at erection (Fig. 11), The convoluted vas deferens localizes in the anterior third of the cirrus pouch and is also seen anteriorly outside it; the extra-saccular portion is 1,0-1,5 mm long and 0,5-0^ mm wide, and neither vitellaria nor testes are seen in the pyramid-shaped area filled by it. The male genital pore opens into the genital atrium anterior to the utero-vaginal portion (Fig. 11). At 240 ja distance from the spot of the utero-vaginal fusion the muscular utero-vaginal canal takes a funnel shape by widening up to 240-300 p in diameter and then joins to the genital atrium (Fig. 12). Neither the utero-vaginal canal, nor the cirrus is bearing cuticular spines.' The uterus forms 11-15 convolutions between cirrus pouch and ovarian isthmus, and 3-4 convolutions posterior to the isthmus. The lumen of the uterus is 100-120 p in diameter, its wall is surrounded with very well developed uterine glands (Fig. 13). The vagina is 5-6 mm long, 40 p in diameter, surrounded by a very thin layer of glandular cells stain deeper (Fig. 13). The vagina takes a slightly undulating course in the median line of the body towards the isthmus of the ovary, and distends to form a seminal receptacle in level with the isthmus. The seminal receptacle 350-440 x 160-200 p in size, localizes behind the ovarian isthmus and bends obliquely over the right lobe of the ovary (Figs. 14 and 15). The ovary is H-shaped, 3-4 mm long and fills the entire space within the medullary parenchyma. The intrinsic structure of the ovary is characteristically reticular (Figs. 14-16). The posterior part of the ovarian lobes is longer, whereas the anterior part is thicker, compared to one another. The isthmus is 300-400 p in diameter. Many vitellaria surround the poles of the posterior lobes. The bulky Mehlis gland, 0,8-1,0 mm in diameter, fills the entire space between posterior ovarian lobes and postovarian vitellaria (Fig. 16), The ootyp localizes in the posterior part of the ovarian isthmus, behind the seminal receptacle. The vitelloduct and oviduct both open into the ootyp and at this spot commences the- uterus. Vitellaria localizing in the anterior third of the body are 80-96 •a,those localizing anterior to the cirrus pouch are 100-140 p in diameter. There are about 500 postovarian vitelline follicles, 80-140 ,u in diameter each. The eggs are small, 48-51 by 29-33 u in size. Discussion The present findings clearly indicate that the carp parasite K. sinensis has fairly widely spread in the pond farms located in North-Eastern Hungary and generally in the catchment area of the river Tisza, whereas its spread to the Danube watershed area is now in the initial phase. If the geographical localization of the distribution area is taken into consideration, it is clear that the parasite entered the country from the Trans-Carpathian area of the Soviet Union via the river Tisza. Since no carps were imported to Hungary in the recent past, introduction of K. sinensis with imported hosts can be excluded. In Poland (PANCZIK and ZELAZNY, 1974) and the German Democratic Republic Figs. 9-18: Transversal sections of Khawia sinensis (9: section at the level of the first third of the body; 10: section at the level anteriorly to the cirrus pouch; 11: section at the level of atrium genitale; 12: enter of the uterovaginal canal into the genital atrium; 13: position of the uterus convolutions and the vagina posteriorly to the cirrus pouch; 14: section at the level of the isthmus of ovary; 15: receptaculum seminis under the isthmus of ovary; 16: section of the Mehlis'gland; 17: group of postovarian vitellaria; 18: terminal excretory duct, - 3-18 Photo MOLNÁR, K. )