In 1858 he began studies of the life history of the Dipterous family Oestridae; the result was the publication in 1863 of “Monographie der Oestriden”.
Subsequent investigations into the metamorphoses of the entire order resulted in the publication of System of Diptera “based upon recent advances in anatomy and embryology”,which appeared in 1883.
The system which with a review by Dr. Sharp appears in the “Cambridge Natural History” Insects part 1 p. 175 divides the class into no fewer than 17 orders, the old Linnean “Neuroptera” furnishing 7 of these.
[clarification needed] Brauer next worked on Tachinidae and other parasitic Diptera on which he published a treatise, in collaboration with Herr.
Brauer identified the Phorid flies collected by the German medical doctor Hermann Reinhard, associated with exhumed bodies from Saxonia, thus contributing to a classic early work of forensic entomology Beiträge zur Gräberfauna.