We sought components that function in morphogenetic events downstream from the segmentation pathway in Drosophila embryos, so we examined mutations that affect development of adult hairs and/or bristles to identify a subset that also affect hairs and denticles on the cuticle of first instar larvae. Mutations at 4 of 23 loci surveyed cause distinct abnormalities in these larval structures, and two other loci have more subtle, variable effects. In particular, forked and singed mutants produce complex, allele-specific phenotypes. These loci encode actin-associated proteins and, consistent with that information, mutations cause abnormalities in actin bundles that support nascent hairs and denticles in stage 14-16 embryos. We suggest that interactions between these and other actin-associated proteins are important in generating the diverse shapes of the cuticular specializations seen in both larvae and adults.