As an outgrowth of earlier work done on the genital structures of male Mutillid wasps, the author's conviction that the biology of insects is as much a factor in their taxonomy and phylogeny as morphology led him to assemble all the knowledge regarding their biology and to carry on some minor researches that were included in Part 1 of this bulletin. He reviewed 630 references, listed in the bibliography and undertook a study of the genotypes of the family, reporting the results in Part 2. This bulletin provides descriptions of multiple specimens examined.

"Zoological Record is published annually in separate sections. The first of these is Comprehensive Zoology, followed by sections recording a year's literature relating to a Phylum or Class of the Animal Kingdom. The final section contains the new genera and subgenera indexed in the volume." Each section of a volume lists the sections of that volume.