Date of Award


Document Type


Degree Name

Master of Science

Degree Discipline



Morphological description based on histological technique is a phase of parasitology which has been, in general, neglected. Almost all the previous authors, including the most recent ones such as Bychowsky (1957), Caballero, Blavo-Hollis and Orocott (1955), Chauhan (1953), Hargis (1959), Jain (I960), Llewellyn (1941), Meserve (19 37), Mizelle (193#, 1955), Price (1959), Ramalingam (1953), and Sproston (1946) have placed great emphasis on external morphology; particularly, on the cuticularized or sclerotized parts of the body such as haptoral anchors, clamp sclerites, copulatory apparatus, etc. These hard parts are, of course, of special value as systematic criteria. The internal anatomy, especially the genitalia, is also of great taxonomic value, although as pointed out by Brinkmann (1952) not much attention has been paid to them by the majority of helminthologists. Some authors, however, including Saint-Remy (1B90), Cerfontaine (1&95), Brinkmann (1942), Palombi (1943), and Yamaguti (1936), have endeavored to work out the details of the internal anatomy of some species.

For the purpose of orientation, the taxonomical history and general morphology of the organism are given.

The trematodes were named by Rudolphi in 1B0R, as an order, which included the following genera: Monostomata, Amphistomata , Pistoma and Polystomata. In l££5, van Beneden proposed the term, monogeneses, for trematodes which develope without metamorphosis and digeneses for those which develope with metamorphosis. The former category generally consisted of ectoparasites and the latter, exclusively, of endoparasites. In 1#63, Carus proposed the terms, Monogenea and Pigenea, respectively, to replace the two terms of van Beneden. In 1&92, Monticelli divided the order Trematoda into the suborders Heterocotylea, Aspidocotylea, and Malacotylea. The suborder Heterocotylea coincides with the Monogenea (Pratt, 1900). The Aspidocotylea and the Malacotylea are divisions of the Digenea. Odhner (1912) divided the Monogenea of Carus into the Polyopisthocotylea and Monopisthocotylea, respectively, on the basis of the presence or absence of a genito-intestinal canal. According to Fuhrmann (192$), the Monogenea and Digenea of Carus are accepted as orders and the order Trematoda Rudolphi, is elevated to the status of class. The order Monogenea Carus, as given by Fuhrmann, embraces three suborders, Monopisthodiscinea, Monoposthocotylinea, and Polyopisthocotylea. Price (1937) prefers the divisions Monopisthocotylea and Polyopisthocotylea of Odhner as suborders to those of Fuhrmann.

Committee Chair/Advisor

J. S. Berry


Prairie View Agricultural and Mechanical College


© 2021 Prairie View A & M University

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Date of Digitization


Contributing Institution

John B Coleman Library

City of Publication

Prairie View




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