an arrondissement of the department of the Jura, in France, 712 square miles in extent. It is divided into eleven cantons, and subdivided into 298 communes, inhabited by 107,500 persons. The capital is the city of the same name. It is situated in a mountainous country, on the banks of the river Baille, and surrounded with picturesque but barren rocks, amongst which are some salt springs, and establishments for procuring refined salt. It contains 860 houses, and 6200 inhabitants. Long. 5° 30'. E. Lat. 46° 36'. N.