Buhl Flying Bull Pup
The only established airplane manufacturer of significance to succeed with a single-seates designed specifically to meet the depression was the Buhl Aircraft Co. of Detroit, Michigan. It marketed the 45-hp Flying Bull Pup in 1931 and sold over 100.
Note the windows in the wing root to give the pilot some downward visibility. While more than 100 were sold, they weren't enough to keep the firm in business.