1927- Twenties day dresses became any time dresses which were more like semi formal street clothes and afternoon frocks than work wear. http://www.vintagedancer.com/1920s/1920s-day-house-dresses-aprons/
The dresses are narrow, shapeless, and have high hemlines compared to earlier times. They are decorated with patterns and designs that can be linked to the Art Deco movement. Hats and hairstyles are obviously 1920s.