A newborn male is found to have urethral openings along the ventral surface of the pains. The physician explains to the parents that the bilateral structures that should have fused in the midline failed to fuse completely, and this resulted in the defect. The parents are very concerned,but the physician reassures them that this can easily be surgically corrected. Which of the following structures in a female normally develop from the same structure that failed to fuse in this buy?