Infected periodical cicadas, Magicicada cassini (Cicadidae: Homoptera), that are developing resting spores of the fungus Massospora cicadina (Entomophthorales) invade new habitat (nearby young trees) about as readily as do uninfected cicadas, although this may not be true for another periodical cicada species, M. septendecim . Proportions of the two sexes infected by the fungus are variable in different situations. Infected females do not oviposit, although they readily mate. Mated females tend to disperse. In M. cassini , males may also disperse en masse, especially if crowded. This may help certain individuals to escape infection in the current generation, but it also serves to spread the resting spores to newly invaded habitat, where they will infect emerging cicada nymphs of the following generation.