What is Proprios?

Legal Definition
In Spanish and Mexican law. Productive lands, the usufruct of which had been set apart to the several municipalities for the purpose of defraying the charges of their respective governments. Sheldon v. Milmo, 90 Tex. 1, 36 S. W. 413; Hart v. Burnett, 15 Cal. 554.
-- Black's Law Dictionary
Legal Definition
Same as Propios.
-- Ballentine's Law Dictionary