Exhibitions held at irregular intervals; first exhibition of season held in Jan. or Feb., second show of the season held in the spring, either March, April, or May.
Jan. 1873-Jan./Feb. 1879 are unnumbered; 1880 called 21st.
Some exhibitions after 1909 were given numbers that had already been used prior to 1909.
Seventieth exhibition called also: American exhibition of the International Society of Sculptors, Painters, and Gravers of London, April 4-23, 1904.
