in chiromancy, is the technical word for the eminences at the roots of the fingers. That at the root of the
thumb is the Mont de Mars.
index finger is the Mont de Jupiter.
long finger is the Mont de Saturne.
ring finger is the Mont de Soleil.
little finger is the Mont de Venus.
There are two others: one between the thumb and index finger, called the Mont de Mercure, and one opposite called the Mont de Lune. (See Finger.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894