Mandibles of females of 10 species of mosquitoes from five genera; hypopharynx of females of 26 species from 11 genera; and laciniae of females of 31 species from 14 genera, were examined using scanning electron microscopy. Mandibular teeth are present in
Anophelesand Armigeresfemales, but absent in Aedes, Culiseta, and Culex. Interdigitating cuticular projections are present at the tip of the hypopharynx in all females examined. The salivary canal is open both at the tip as well as dorsally along a longitudinal slit. The average number of lateral teeth on the maxillary stylets varies according to species. Mesial and vestigial teeth are present in some species. There is no correlation between number of maxillary teeth and specific hosts of mosquito species. The function of stylet structure in feeding is discussed.