The poll tax mentioned in this article shall be one dollar and fifty cents upon each male inhabitant of the state, over the age of twenty-one years, and under the age of forty-five years, who would not now be exempt by law; but the legislature is authorized to increase the maximum age fixed in this section to not more than sixty years. Such poll tax shall become due and payable on the first day of October in each year, and become delinquent on the first day of the next succeeding February, but no legal process, nor any fee or commission shall be allowed for the collection thereof. The tax collector shall make returns of poll tax collections separate from other collections.