The department of public libraries shall have the function of administering a county public library system with a central book depository, branches and stations, and bookmobile services for rural areas not adequately served by such branches and stations. Such branches and stations may be established and maintained in public schools and other public buildings in the county with the consent of the governmental authorities having jurisdiction over such buildings and in such other buildings as the council may provide. (Mont. Co. Code 1965, § 2-51.)