The third panel contains different types of the 1949 and 1950 South Dakota waterfowl stamps with horizontal and vertical safety paper. The only known full sheet of the 1950 stamp is on display (see Figures 7, 8 and 9).
Figure 7. 1949 South Dakota waterfowl stamp, Type I printed on vertical safety paper.
Figure 8. Type II printed on horizontal safety paper.
Figure 9. This proof block of the 1950 South Dakota waterfowl stamp is the largest multiple recorded.