Much of the correspondence is in the form of letters received and sent. Letters received are arranged according to author of the letter, with each author separated into a folder. Of the six folders of correspondence sent by Lemonnier, only two contain original letters. The other four folders contain transcripts of letters Lemonnier sent to his family in France between 1859 and 1874. The originals of these transcriptions are kept in the Archives de la Roche in France and were sent to Notre Dame by Henri Lemonnier-Dubourg between 1938 and 1940. Included with these transcriptions is a genealogy of the Lemonnier family. All of these transcriptions, as well as much of the correspondence, are in French.