Of the 15 or 16 probable species of the genus Dermestes occurring in North America, the larvae of 11 have been studied by the writer. In the course of these studies certain, and it is believed new, characters of taxonomic importance have been found. It has also been noted that these characters, along with others, pass through various stages of development, sometimes gradually, sometimes abruptly, as the larva approaches maturity. It is the purpose of this paper to bring these new characters and observations to the attention of those interested in coleopterous larvae and to those particularly interested in this important economic group. All specimens studied are preserved in the United States National Museum. The identification of the specimens was checked as closely as possible, and the only larvae used were those definitely associated with adults, or from which adults had been reared.