This study investigated the postcyclic transmission of Neoechinorhynchus cylindratus and Leptorhynchoides thecatus, including gravid female worms, between largemouth bass. Twenty largemouth bass were each given 10 individuals of N. cylindratus taken from the enteric system of largemouth bass, and 10 largemouth bass were each given 10 individuals of L. thecatus taken from the enteric system of largemouth bass. After 2 wk, bass were necropsied and examined for the presence of worms. Six and a half percent of N. cylindratus and 11% of L. thecatus were successfully transferred postcyclically, thus demonstrating that postcyclic transmission of N. cylindratus and L. thecatus, including gravid females, does occur. This provides a potential explanation for the high prevalence of these acanthocephalans often observed in large, exclusively piscivorous largemouth bass.