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Not AvailableThe polynemid fishery which is not of a big magnitude has shown rise and fall in the catches during the last 30 years from 195Sto 1985. The fishery whenever dropped in the north west coast showed improvement along the east coast- though represented by 9 species most of which have fisheries of very small magnitude, the overall fishery is supported mainly by (Polydactylus Indicus i'Dara') and to a lesser extent by Eleutheronema tetradactylum (Rawas') both growing to over a meter in length and weighing more than I8kg. Because of the dominance of P. indicus, fluctuations in Its catches are reflected on the fluctuations in the total polynemid catches. The decline in the catches in sixties is attributed to the heavy landings of 'Chelna' which are nothing but juveniles of 'Dara' in the fifties and sixties by the commercial trawlers. Added to this are certain biological facts 'Dara' matures in the IVth year and is a gonochoristic hermaphrodite in which the ovarian part of ovotestis becomes active alternatively with the testicular part and In this process the period for an individual to reproduce the progeny is reduced to half- Hermaphrodites are also encountered in other polynemid speciesNot Availabl