It shall be the duty of the County Assessor and the Sheriff as required under State law to collect a Municipal head tax on dogs above the age of six months, such tax being six dollars ($6.00) on each dog whether the dog be male or female. The six dollars ($6.00) tax head on each dog is payable yearly. If the tax is not paid within fifteen days of its assessment the Sheriff shall have the right to impound the dog for such services and an extra one dollar and fifty cents ($1.50) shall be added to the fee. The Sheriff shall keep the dog for fifteen days after which if the delinquent taxpayer does not pay this tax the Sheriff shall sell the dog and after taking out the money required for the tax and upkeep of the dog, return the sum to the delinquent taxpayer. Should the Sheriff fail to sell the dog he shall dispose of it.