15thc perception on swallowtail merlons?

[CaryR]

         

These two images are potentially interesting. I originally found the first one on Pinterest, which comes from this You are not allowed to view links. Register or Login to view. about medieval gardens that just says it's an engraving. I tried a reverse image search but couldn't find original sources anywhere. Then I found the second image, which is similar but again there are no sources. Just throwing that out there in case anyone else has any luck tracking down more info. But it may be a dead end, and the dates of their creation are unknown.