Objectives. To determine the natural crustacean host

the Paragonimus species

and to investigate the potential host-parasite relationship between Manipur Paragonimus and some of the laboratory animals.Methods. The laboratory animals such as puppies

albino rats and Swiss mice were infected orally with metacercariae isolated from the fresh water crabs

Potamiscus manipurensis. The fecal specimens of the experimentally infected animals were examined microscopically for Paragonimus eggs at regular intervals. The animals were autopsied on days 35 - 328 after infection and the isolated worms were flattened between glass slides and fixed in 70% alcohol. The worms were stained with carmine and mounted with Canada balsam for morphological studies. The eggs were collected in 5% formol saline solution for microscopy. The flukes were classified into 4 developmental stages.Results. A total of 11 worms

5 mature

5 immature and 1 pre - adult were recovered. The morphological features of the metacercariae

worms and eggs were similar to those of Paragonimus heterotremus.Conclusion. Manipur is one of the rare areas in the world where Paragonimus heterotremus is prevalent and the puppies are ideal experimental animal host. This species may be one of the important causes of paragonimia-sis in animals and humans in Manipur.