Nurse cells in the ovaries of adults of Anopheles quadrimaculatus. Species A, were used to prepare a polytene chromosome map. The chromosome quality is superior to that of salivary glands, and it is easier to use adults rather than larvae for cytological analysis of field populations. The most reliable homologies between the salivary and ovarian maps are located in the distal ends of the respective arms, and one homologous region is a prominent landmark in all of the members of the nearctic Maculipennis complex and related species. The left arm of chromosome 3 is uniquely dimorphic. The homokaryotype for 3L1 is synonymous with 3L of the published map of salivary gland polytenes. The 3L heterokaryotype is mostly asynaptic, except for two small homologous, synaptic areas, one of which is inverted. Each homokaryotype contains a unique, diffuse puff that is adjacent to the centromere.