Many county transcriptions stopped before 1879 because WPA funding had ended. There are some gaps in the records either because the original was destroyed or the transcription is missing. These gaps are noted in the folder lists. The Essays Series is made up of essays written during the survey and cover all areas of the survey. The Forms , Instructions , and Lists series are made up of items created for the administration of the survey.
Administrative reports make up the bulk of the Reports Series.
The Research Series primarily consists of notes with a few memos and maps. The bulk of the notes deal with the offices and functions of county government and Missouri statutes. These notes were possibly made by WPA field workers in an effort to understand the workings of county government and state law.