All previous published equivalent widths of the Martian CO2 bands including the 1967 apparition coverage at McDonald Observatory are reduced to CO2 abundances using the same curve of growth parameters. The corresponding CO2 partial pressures (assuming a pure CO2 atmosphere), along with the regression curves of the north polar cap, are presented as functions of Martian heliocentric longitudes, Ls. A correlation is noted between the maximum CO2 abundance and minimum north cap diameter and the decrease in CO2 abundance when the northern polar haze begins to reform. Preliminary results of the 1969 apparition coverage at McDonald Observatory are also presented.