ABSTRACT. An unnamed pair of setae (two pairs in some species groups) on the larval cervical membrane in all genera of Culicidae examined is described and illustrated, and names are proposed (18, 19-C). Homology in Dixinae with 16, 17-C is revised. Their apparent function is suggested. Their taxonomic importance and possible phylogenetic significance are discussed, with special reference to Aedes subgenera Ochlerotatus and Finlaya.