Honorary Membership was limited to 10 from 1890-1900, and to 15 from 1901 onwards. Corresponding Membership was a lesser class of Honoris causa membership in the early years. A few honorary members, such as Barnard, were first made corresponding members for a short time before being recommissioned as honorary members.
Nation(s) |
Start | End | |
|---|---|---|---|
| Sandage, Dr. Allan R. | USA | 1975 | 2010 |
| Harrison, Mr. Henry | USA | 1913 | 1929 |
| Bowen, Dr. Ira S. | USA | 1956 | 1973 |
| Holden, Dr. Edward S. | USA | 1891 | 1914 |
| Joy, Dr. Alfred H. | USA | 1961 | 1973 |
| Swift, Dr. Lewis A. | USA | 1903 | 1913 |
| Kedzie, Mr. John Hume | USA | 1890 | 1903 |
| Hale, Dr. George Ellery | USA | 1900 | 1938 |
| Baldwin, Dr. Ralph Belknap | USA | 1980 | 2011 |
| Campbell, Prof. William Wallace | USA | 1905 | 1938 |