The van Niel papers primarily document C.B. van Niel's career at the Hopkins Marine Station of Stanford University, his participation in preeminent scientific associations, and his role as a leader in the field of microbiology. The papers include American Type Culture Collection (ATCC) papers, 1960-1964; teaching materials, 1929-1968; publications, 1923-1972 and a comprehensive list of all his publications; research files; correspondence 1924-1977; photographs; medals; and audiotapes of lectures, 1962. Correspondents include C.E. Clifton, Seymour S. Cohen (1917- ), Lois Epel, Helge Larsen, Jack London [a student from UCLA], Beryl V. Daniel, J.R. Porter, Hosmer W. Stone, Charles H. Walkinshaw, E.G. Pringsheim (1881- ), Selman A. Waksman (1888-1973), and Vernon Bryson (1913- ).