Medieval parchment —animal skin — that was stabbed, cut and stitched up. If the parchment maker pushed too hard while removing the unwanted parts like hair or fleshy bits, he would cut right through the surface. While some cuts were simply stitched up with a thin parchment cord, it also happened that book producers turned these defects into art.
Interesting to see the 2 different handwriting on this. Title Theological miscellany; the Prophecies of Merlin Origin England Date Last quarter of the 13th century or 1st quarter of the 14th century Language Latin and French (Anglo-Norman) Script Gothic cursive