I love this old time home shot video in black and white. It really gives you a sense of the styles of 1931, full one piece suits made of wool. Even the little toddlers are wearing one piece wool suits. Towards the middle there is a young woman wearing what are called beach Pyjamas. This was considered casual beach wear. The music is very fitting for this piece.
In History of 20th Century Fashion, by Elizabeth Ewing she states, "Beach pyjamas, with flaring legs, had been anticipated by slim lounging pyjamas, which Chanel was making in the early 'twenties and which were soon being worn by the fashionable. The beach ones, however, had a life all their own and were worn exclusively on beaches everywhere, usually with backless sun-tops or sleeveless blouses....It was the beginning of a new category of clothes, the start of the 'casuals' which were to have a great vogue in future years."
Bette Davis in a swimsuit, and Joan Blondell in beach pyjamas in the early 1930's. The fabulous costumes are by Warner Brothers genius Orry-Kelly.
For more eye candy on the Beach Pyjama, there is a wonderful blog (in French) located here. While I can't read it because my french is really really rusty, I can certainly enjoy the pictures!