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

As the structure of the genital sucker has always been an important argument as a generic feature therefore it is necessary to examine whether C. indicum has a Cotylophoron type of genital opening. The Cotylophoron type of genital opening is characterized by the presence of a great number of radial muscle elements (Fig. 4) and, at the same time, by a fairly poor longitudinal musculature. In case of the genital opening of C. indicum the radial musculature is weak but the longitudinal one is strongly developed (Figs. 1, 5). Measurements of the genital opening of the species of the genus Cotylophoron are usually twice as bigger (Figs. 2, 4) than that of C. indicum (Figs. 1, 5). The genital opening clearly deliminates from the surrounding tissues of the species Cotylophoron, in case of C. indicum it does not. Pars prostatica strongly developed in C. indicum (prostatic cells are situated in several rows /Figs. 1, 5/), while in Cotylophoron spp. it is weak or moderately developed (Figs. 2, 4). Finally, there is as difference in the position of genital pore of the species of C. indicum and of Cotylophoron spp. Accordingly, the structure of the genital opening of C. indicum reminds me rather of the Epiclitum than that'of the Cotylophoron type and I presume that the differences mentioned above support this belief. Beside the differences that can be discovered in the structure of the genital opening, the presence of d. e. 2 muscle layer in the acetabulum also suggests that C. indicum should be excluded from the genus Cotylophoron (Price and Mcintosh, 1953). Namely, the structure of the acetabulum of the Cotylophoron type seems to be constant for there are no literary data to report the presence of a d. e. 2 muscle layer. In 1970 SINGH described a new genus and species, Srivastavaia indica whose validity should be examined in the light of the knowledge of histo-morphological details of C. in dicum . The structure of the acetabulum of S. indica was seemingly interpreted erroneously because d. e. 2 muscle layer can be found in it according to the figure attached to the text of SINGH' s paper. Namely, in case when a d. e. 2 muscle layer is absent the number of muscle units in d.e.l andv.e. muscle layers is usually the same. Accordingly, S. indica

, has Paramphistomum and not Streptocoelium type of acetabulum. Due to a similarity of structure and measurement as well as to the presence of a well developed pars prostatica, all of which were expressed in connection with the genital opening of C. indicum, characterize S. indica

' s as well. SINGH (1970) himself made mention of the fact that S. indica showed some resemblances to Paramphistomum thapari (= C. indicum) especiaUy in structure of the pharynx, genital opening, acetabulum and position of the excretory and Laurer' s canals.* Differences were emphasized, however, between these species in the number of muscle elements of d. e. 2 muscle layer and the development of sphincter papiUae. The structure of the acetabulum of S. indica was discussed above to point out that it is of Paramphistomum type that is the same as P. thapari

' s (= C. indicum

). The presence of a sphincter papulae mentioned by SINGH* (1970) in the genital opening seems to be a misinterpretation of a given histological structure because such a sphincter is not found in the genital atrium of P. thapari (= C. indicum

) that the structure of the genital atrium of S. indica was compared with. Laurer* s and excretory canals, according to SINGH (1970) did not cross each other (p. 124) but there seems to be a controversy about two points. It was mentioned (p. 125) that these two canals show some resemblance in S. indica and P. thapari (= C. indicum) and later (p. 126) he wrote "Laurer' s canal opens posterior to the excretory pore without crossing the excretory duct". On the one hand if there exists a resemblance in the position of these two canals in the species in question, then there is a crossing because in P. thapari (= C. indi cum) these canals cross each other and on the other it is generally accepted that crossing exists not only in case when Laurer' s canal passes through the excretory duct only but also when a crossing developes in the region of the excretory bladder. Accordingly, excretory and Laurer' s canals cross each other in S. indica

. On the basis of the similarities of the histo-morphological features of C. indicum (= P. thapari

) and S. indica, pronounced above I regard these species to be synonymous with P. epiclitum. * SINGH did not examine the type specimens of P. thapari (= C. indicum

) he had compared S. indica with an amphistome designated by himself to P. thapari.