Assessments against unplatted or partially platted lands; extent of benefit district

Where any of the improvements specified in this act are to be made upon streets or avenues, and the pieces of land abutting on such improvement shall not be divided into lots or blocks, the assessments for such improvement shall be made on the piece or pieces of ground adjoining such improvement or through which the same may be located to the distance of 300 feet from the street or avenue upon which such improvements are made extending along the street or avenue the distance improved or to be improved: Provided, That where the street or avenue to be improved runs partially through platted ground and partially through unplatted ground, the assessments for the payment of the cost of the construction of the improvement on the street or avenue running through the unplatted ground shall be levied on the lots and pieces of ground along said street or avenue on either side thereof, to the same distance on either side of said street or avenue as the levy is made where the street or avenue to be improved runs through platted ground: Provided, That in no case shall the benefit district extend more than half way to the street or public highway parallel with and next to the public ground to be improved.