Pince-nez
Glasses with no arms, held on by a spring clip that pinches the nose bridge.
Also: nose spectacles
Pince-nez, French for "pinch nose", clip onto the bridge of the nose with a spring or a flexible bar. Popular from the 1840s until the early twentieth century, they were often hung from a cord or chain. They are linked with figures such as the American president Theodore Roosevelt and the writer Anton Chekhov. They fell out of use as arm frames improved, and are now mostly a vintage curiosity.