Life table data were collected for seven generations ofLaplatcris disparRehn. Variation in hatching between generations was negatively correlated with rainfall during fall and winter. Both unrealized natality and mortality during the egg stage were density independent. Nymphal mortality, the key factor related to variation in total mortality, was considered to be largely caused by polyphagous spiders, and was density independent. Adult mortality, mainly caused by parasites and predators, was density dependent, compensatory with the previous mortalities, and important as a regulating factor in population density.