In any county now having a county court established by Chapter 131 of the laws of 1926 and having only one judicial district therein and in which the assessed valuation of real and personal property has fallen below seventeen million dollars but exceeds fifteen million dollars according to the assessment of 1932, and in which the urban population exceeds the rural population, and having therein a municipality in excess of 15,000 population, according to the last federal census, said county court shall remain in existence until abolished by a direct act of the legislature or by an election as now provided by law.