Abstract
The worm burden distributions of a macrofilarial nematode, Ochoterenella digiticauda, and a gastroenteric digenean, Mesocoelium monas, were examined in a naturally infected population of Bufo marinus from Jamaica. Both parasite species had over-dispersed distributions which were well described by the negative binomial probability model (k = 0·35 for 0. digiticauda; and k = 0·59 for M. monas). The intensity distributions of the two parasites were uncorrelated: there was no significant association between the intensity (whether absolute or relative) of infection of either parasite in individual hosts. It is suggested that different, and parasite species-specific, factors of the host interaction are involved in generating the separate distributions of the two parasite species.