On any lot running through from one street to another, the front of the lot shall, for the purposes of this chapter, be considered that frontage upon which the majority of the buildings in the same block front, but, in case there has been no clearly defined building frontage established, the owner may, when applying for a building permit, specify which lot line is to be considered the front lot line for the purposes of this chapter.

In the case of lots fronting on the turnaround of a cul-de-sac street or fronting upon any other curved street, lot frontage (as distinguished from lot width) may equal but shall be no less than two-thirds (2/3) of the required lot width as set forth in the schedule (see Section 37-63), and further provided that no lot shall have a frontage of less than fifty (50) feet.