(a) It shall be the duty of the county clerk of the county to extend the taxes annually upon the tax books of the county until the levy is exhausted. For his services he shall receive a commission of one-half of one percent (½ of 1%) of the amount so extended.
(b) It shall then be the duty of the collector to collect each year the taxes extended upon the book along with the other taxes until the entire levy is exhausted. For his services in making such collections, the collector shall receive a commission of one-half of one percent (½ of 1%), and the taxes shall by the collector be paid over to the depository of the district at the same time that he pays over the county funds.
(c) If any collector shall fail to collect the improvement tax along with the other taxes, he shall be subject to a penalty of twenty-five dollars ($25.00) for each instance in which he shall collect from an individual the other taxes and omit the improvement tax, unless the improvement tax has been enjoined by a court of competent jurisdiction to be recovered in a suit brought by the commissioners to the use of the district; and the county clerk shall be subject to a like penalty for each tract of land that he omits from the tax books.