The magnitude of variations in the life cycle and form changes which are met with when the Coleoptera and the Strepsiptera are considered as a group are hardly exceeded by any other group of insects. When we remember that there are now considered to be more than one hundred families of Coleoptera containing, in all, over one hundred and fifty thousand species, it is not surprising that there is a great amount of variation. Some of the standard works on the Coleoptera might lead one to believe that beetles have no larval or pupal stages, for they are not mentioned. When Buetenmuller published his catalogue of the described transformations in 1891, the eggs had been described for 52 species, the larvae for 368, and the pupae for 96 species in North America. While a considerable amount of progress has been made since that time it has been only during recent years that attempts have been made to correlate the knowledge of the transformations of even the smaller groups.