Series 1, Philadelphian Society Records, 1855-1946, consists of bound volumes and files containing the Society's charter and by-laws, membership lists, and minutes of Society, board, and cabinet (undergraduate officer) meetings. (The bulk of the collection ends in 1930, while board minutes and correspondence continue until 1946, relating to business matters of the Princeton Summer Camp.) Files contain reports of general secretaries and committee chairs to the board and the cabinet. Committee records include bound volumes and files of membership and financial information, including information on the annual campus fund-raising drive, plus material relating to the Society's religious and social work. Among the Society's publications are several journals, the Student Handbook, and a newspaper. Files regarding Buchmanism contain testimony before President Hibben's committee of 1926, the committee's report, and clippings and correspondence related to the controversy. Several scrapbooks include correspondence, circulars and clippings regarding the Society's work on and off campus.

The Meeting Minutes series contains the meeting minutes of the Ladies Auxiliary. Included are annual meetings of the entire body, more frequent but less well-attended regular meetings, and executive board meetings. Each set of minutes notes the type of meeting, and contains the date of the meeting, its location, a list of attendees, and issues discussed or voted upon. Until 1915 the minutes are handwritten in bound ledgers by the Ladies Auxiliary Secretary.

The Correspondence series consists of the correspondence of the Ladies Auxiliary. From 1903-1947 the correspondence originates from a variety of Auxiliary members, however after 1983 only correspondence of the presidents of the Auxiliary is present. The correspondence covers a diverse range of topics, such as the planning and construction of a new infirmary building in the early 1920s, requests for financial assistance from students with overwhelming medical expenses, and the printing of William K. Selden's 1991 book The Heritage of Isabella McCosh: a History of the Health Services at Princeton University. One packet of correspondence labeled "Letters of Special Interest" contains handwritten notes from Mrs. Woodrow Wilson, among others.

The General Files series contains files of the Ladies Auxiliary documenting a variety of topics. Within the folders are mixed materials, such as clippings, pamphlets, and some correspondence. Particularly notable materials include an 8"x10" photograph of an Eastman Johnson portrait of Isabella McCosh held by the Princeton Art Museum, along with provenance information and a conservation estimate; as well as a 1912 proposal for a new infirmary building that was never built including floor plans and an artist's rendering. Also included are two visitor registers to the McCosh Infirmary.

The Annual Reports series contains the Annual Reports of the Ladies Auxiliary, which provide yearly financial information as well as a summary of the Auxiliary's activities and ongoing projects. The content of the reports provide a sense of the Isabella McCosh Infirmary's continual growth and expanding activities.

Series 1: Diplomas from the Princeton University Archives Oversize Collection, 1749-1998 (bulk 1749-1926) consists of 183 original diplomas and photostats, as well as a small number of blank, sample or spoiled diplomas.

Series 2: Blank and Unused Diplomas, 1863-1916, contains approximately 30 diplomas. Some of the diplomas are signed by president John Maclean, one is signed by president James Carnahan, and many are signed by trustees. None of the diplomas are filled out with students' names. A few of the diplomas appear to be drafts. The series also includes one sheet of instructions for preparing diplomas for engineering students (1916).

Series 2: Associations contains records of various geology-related associations or organizations, including some records of the Geology Club at Princeton; the Princeton Geological Association; and the Geological Society of America; as well as the records of the American Institute of Geonomy and Natural Resources (an organization led by Princeton faculty members, though it was not headquartered at Princeton).