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 | |
|---|---|---|---|
| Schlesinger, Dr. Frank | USA | 1916 | 1943 |
| Bowen, Dr. Ira S. | USA | 1956 | 1973 |
| Rogers, Prof. William A. | USA | 1894 | 1898 |
| Holden, Dr. Edward S. | USA | 1891 | 1914 |
| Burnham, Prof. Sherburne Wesley | USA | 1891 | 1921 |
| Joy, Dr. Alfred H. | USA | 1961 | 1973 |
| Pickering, Mr. William Henry | USA | 1894 | 1938 |
| Hubble, Dr. Edwin Powell | USA | 1951 | 1953 |
| Lowell, Prof. Percival Lawrence | USA | 1916 | 1916 |
| Barnard, Dr. Edward Emerson | USA | 1901 | 1923 |