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 | |
|---|---|---|---|
| Winder, Mr. Daniel K. | USA/Canada | 1890 | 1891 |
| Goldie, Mr. John | Canada | 1890 | 1891 |
| Pettit, Mr. H. | Canada | 1890 | 1890 |
| Shearmen, Mr. T.S.H. | Canada | 1890 | 1900 |
| Kirkwood, Dr. Daniel | USA | 1890 | 1895 |