Once upon a time ...
Petit Montrouge and Grand Montrouge.
Petit Montrouge, which once extended up to the Parisian Montparnasse district, was annexed under Napoleon III from a rapidly growing Paris, later becoming the 14th arrondissement.
Grand Montrouge then turned to its neighboring towns and began eating up their land. This expansion enabled it to accommodate some of the industrial companies that flourished between the two wars, such as the printing company Draeger and the landing gear manufacturer Hispano-Messier (now the Safran group)